Thioimidazolidine derivatives as light stabilizers for polymers

ABSTRACT

A compound of the formula (I) wherein G 1 , G 2 , G 3  and G 4  are independently of one another C 1 -C 18 alkyl or C 5 -C 12 cycloalkyl or the radicals G 1  and G 2  and the radicals G 3  and G 4  form independently of one another, together with the carbon atom they are attached to, C 5 -C 12 cycloalkyl; R is hydrogen, C 1 -C 18 alkyl, oxyl, —OH, —CH 2 CN, C 3 -C 6 alkenyl, C 3 -C 8 alkynyl, C 7 -C 12 phenylalkyl unsubstituted or substituted on the phenyl radical by C 1 -C 4 alkyl and/or C 1 -C 4 alkoxy; C 1 -C 8 acyl, C 1 -C 18 alkoxy, C 1 -C 18 hydroxyalkoxy, C 2 -C 18 alkenyloxy, C 5 -C 12 cycloalkoxy, C 7 -C 12 phenylalkoxy unsubstituted or substituted on the phenyl radical by C 1 -C 4 alkyl and/or C 1 -C 4 alkoxy; C 1 -C 18 alkanoyloxy, (C 1 -C 18 alkoxy)carbonyl, glycidyl or a group —CH 2 CH(OH)(G) with G being hydrogen, methyl or phenyl; n is 1, 2, 3 or 4; and X is an organic radical of a valency equal to n; and when n is 2, 3 or 4, each of the radicals G 1 , G 2 , G 3 , G 4  and R can have the same or a different meaning in the units of the formula (II), is useful for stabilizing an organic material against degradation induced by light, heat or oxidation

The present invention relates to thioimidazolidine derivatives, to their use as light stabilizers, heat stabilizers and oxidation stabilizers for organic materials, particularly synthetic polymers, and to the organic materials thus stabilized.

The stabilization of a photographic material with a particular thioimidazolidine derivative is for example described in DE-A-2,042,533. Oxoimidazolidine derivatives are for example disclosed in DE-A-2,621,947, U.S. Pat. Nos. 3,532,703 and 3,971,757.

The present invention relates in particular to a compound of the formula (I)

wherein

-   G₁, G₂, G₃ and G₄ are independently of one another C₁-C₁₈alkyl or     C₅-C₁₂cycloalkyl or the radicals G₁ and G₂ and the radicals G₃ and     G₄ form independently of one another, together with the carbon atom     they are attached to, C₅-C₁₂cycloalkyl; -   R is hydrogen, C₁-C₁₈alkyl, oxyl, —OH, —CH₂CN, C₃-C₆alkenyl,     C₃-C₈alkynyl, C₇-C₁₂phenylalkyl unsubstituted or substituted on the     phenyl radical by C₁-C₄alkyl and/or C₁-C₄alkoxy; C₁-C₈acyl,     C₁-C₁₈alkoxy, C₁-C₁₈hydroxyalkoxy, C₂-C₁₈alkenyloxy,     C₅-C₁₂cycloalkoxy, C₇-C₁₂phenylalkoxy unsubstituted or substituted     on the phenyl radical by C₁-C₄alkyl and/or C₁-C₄alkoxy;     C₁-C₁₈alkanoyloxy, (C₁-C₁₈alkoxy)carbonyl, glycidyl or a group     —CH₂CH(OH)(G) with G being hydrogen, methyl or phenyl; -   n is 1, 2, 3 or 4; and -   X is an organic radical of a valency equal to n with the proviso     that X is different from methyl and ethoxycarbonyl; and -   when n is 2, 3 or 4, each of the radicals G₁, G₂, G₃, G₄ and R can     have the same or a different meaning in the units of the formula -   X may be for example different from C₁-C₃alkyl and     (C₁-C₃alkyl)oxycarbonyl, in particular (C₁-C₆alkyl)oxycarbonyl.

Preferred compounds are those wherein

-   when n is 1, X is C₂-C₁₈alkyl, C₂-C₁₈hydroxyalkyl, C₂-C₁₈alkyl     interrupted by oxygen, sulphur or >N—R₀ with R₀ being as defined     below; C₂-C₁₈alkenyl, C₂-C₁₈alkynyl, C₅-C₁₂cycloalkyl unsubstituted     or substituted by —OH, C₁-C₄alkyl and/or C₁-C₄alkoxy; phenyl or     C₇-C₉phenylalkyl unsubstituted or substituted on the phenyl radical     by —OH, C₁-C₄alkyl and/or C₁-C₄alkoxy; or X is one of the groups of     the formulae (II-a) to (II-m) -   Y₁, Y₂, Y₅, Y₆, Y₇ and Y₉ are a direct bond, C₁-C₁₂alkylene,     C₅-C₁₂cycloalkylene or phenylene; -   Y₃, Y₄, Y₈, Y₁₀, Y₁₁ and Y₁₂ are C₂-C₁₂alkylene, C₅-C₁₂cycloalkylene     or phenylene; -   R₁, R₂, R₃, R₄, R₅, R₆, R₇ and R₁₃ are hydrogen, C₁-C₁₈alkyl,     C₂-C₁₈alkyl interrupted by oxygen, sulphur or >N—R₀ with R₀ being as     defined below; C₂-C₁₈alkenyl, C₂-C₁₈alkynyl, C₅-C₁₂cycloalkyl     unsubstituted or substituted by C₁-C₄alkyl and/or C₁-C₄alkoxy;     phenyl unsubstituted or substituted by C₁-C₄alkyl and/or     C₁-C₄alkoxy; or C₇-C₉phenylalkyl unsubstituted or substituted on the     phenyl radical by C₁-C₄alkyl and/or C₁-C₄alkoxy; -   Z₁, Z₂ and Z₃ are independently of one another —O— or >N—R₁₆; -   R₀, R₈, R₉, R₁₀, R₁₁, R₁₂, R₁₄, R₁₅ and R₁₆ are independently of one     another hydrogen, C₁-C₁₈alkyl, C₃-C₁₈alkenyl, C₅-C₁₂cycloalkyl which     is unsubstituted or substituted by C₁-C₄alkyl and/or C₁-C₄alkoxy; or     C₇-C₉phenylalkyl which is unsubstituted or substituted on the phenyl     radical by C₁-C₄alkyl and/or C₁-C₄alkoxy; -   with the proviso that the formula (II-b) is different from     ethoxycarbonyl; -   when n is 2, X is C₂-C₁₂alkylene, C₂-C₁₆alkylene interrupted by     oxygen, sulphur or >N—R₀′ with R₀′ being as defined below;     C₂-C₁₂alkenylene, C₂-C₁₂alkynylene, C₅-C₁₂cycloalkylene,     C₅-C₁₂cycloalkylene-(C₁-C₄alkylene)-C₅-C₁₂cycloalkylene,     C₁-C₄alkylene-(C₅-C₁₂cycloalkylene)-C₁-C₄alkylene, phenylene,     phenylene-(C₁-C₄alkylene)-phenylene or     C₁-C₄alkylene-phenylene-C₁-C₄alkylene, or X is one of the groups of     the formulae (III-a) to (III-j) -   Y₁′, Y₁″, Y₂′, Y₂″, Y₅′, Y₅″, Y₆′, Y₆″, Y₇′ and Y₇″ are     independently of one another a direct bond, C₁-C₁₂alkylene,     C₅-C₁₂cycloalkylene or phenylene; -   Y₃′, Y₃″, Y₄′, Y₄″, Y₈′, Y₈″, Y₁₁′, Y₁₁″, Y₁₂′ and Y₁₂″ are     independently of one another C₂-C₁₂alkylene, C₅-C₁₂cycloalkylene or     phenylene; -   A₁, A₂, A₃, A₄, A₅, A₆, A₇, A₈ and A₉ are C₂-C₁₂alkylene,     C₂-C₁₂alkylene interrupted by oxygen, sulphur or >N—R₀′ with R₀′     being as defined below, C₂-C₁₂alkenylene, C₂-C₁₂alkynylene,     C₅-C₁₂cycloalkylene,     C₅-C₁₂cycloalkylene-(C₁-C₄alkylene)-C₅-C₁₂cycloalkylene,     C₁-C₄alkylene-(C₅-C₁₂cycloalkylene)-C₁-C₄alkylene, phenylene,     phenylene-(C₁-C₄alkylene)-phenylene or     C₁-C₄alkylene-phenylene-C₁-C₄alkylene; and A₁ and A₅ are     additionally a direct bond; -   Z₁′, Z₂′ and Z₃′ are independently of one another —O— or >N—R₁₆′;     and -   R₀′, R₁₄′ and R₁₆′ are independently of one another hydrogen,     C₁-C₁₈alkyl, C₃-C₁₈alkenyl, C₅-C₁₂cycloalkyl which is unsubstituted     or substituted by C₁-C₄alkyl and/or C₁-C₄alkoxy; or C₇-C₉phenylalkyl     which is unsubstituted or substituted on the phenyl radical by     C₁-C₄alkyl and/or C₁-C₄alkoxy: -   when n is 3, X is C₅-C₂₅alkantriyl, C₄-C₁₈triacyl or a group of the     formula (IV); -   Y₁₃′, Y₁₃″ and Y₁₃′″ are independently of one another     C₂-C₁₂alkylene, C₅-C₁₂cycloalkylene or phenylene; -   Z₁″, Z₂″ and Z₃″ are independently of one another —O— or >N—R₁₆″;     and -   R₁₆″ is hydrogen, C₁-C₁₈alkyl, C₃-C₁₈alkenyl, C₅-C₁₂cycloalkyl which     is unsubstituted or substituted by C₁-C₄alkyl and/or C₁-C₄alkoxy; or     C₇-C₉phenylalkyl which is unsubstituted or substituted on the phenyl     radical by C₁-C₄alkyl and/or C₁-C₄alkoxy; and -   when n is 4, X is C₅-C₂₀alkantetrayl, C₆-C₂₂tetraacyl or a group of     the formula (V) -   Y₁₄′ and Y₁₄″ are independently of one another C₂-C₁₂alkylene,     C₅-C₁₂cycloalkylene or phenylene; -   Z₁′″, Z₂′″, M and T are independently of one another —O— or     >N—R₁₆′″, and M and T are additionally —S—; -   R₁₆′″ is hydrogen, C₁-C₁₈alkyl, C₃-C₁₈alkenyl, C₅-C₁₂cycloalkyl     which is unsubstituted or substituted by C₁-C₄alkyl and/or     C₁-C₄alkoxy; or C₇-C₉phenylalkyl which is unsubstituted or     substituted on the phenyl radical by C₁-C₄alkyl and/or C₁-C₄alkoxy;     and -   q is an integer from 2 to 12.

X as an organic radical of a valency equal to n may be for example an aliphatic, cycloaliphatic or aromatic residue optionally containing a heteroatom such as oxygen, sulphur or nitrogen.

Examples of alkyl containing not more than 18 carbon atoms are methyl, ethyl, propyl, isopropyl, butyl, 2-butyl, isobutyl, t-butyl, pentyl, 2-pentyl, hexyl, heptyl, octyl, 2-ethylhexyl, t-octyl, nonyl, decyl, undecyl, dodecyl, tridecyl, tetradecyl, hexadecyl and octadecyl. G₁, G₂, G₃ and G₄ are preferably C₁-C₄alkyl, in particular methyl. One of the preferred meanings of R is C₁-C₄alkyl, in particular methyl. One of the preferred meanings of R₁ is C₁-C₈alkyl such as methyl or 3-heptyl.

An example of C₂-C₁₈hydroxyalkyl is 2-hydroxyethyl.

Examples of C₂-C₁₈alkyl interrupted by oxygen or sulphur, e.g. one or more oxygen or sulphur, are 2-methoxyethyl, 2-ethoxyethyl, 3-methoxypropyl, 3-ethoxypropyl, 3-butoxypropyl, 3-octyloxypropyl, 4-methoxybutyl, 2-methylthioethyl, 2-ethylthioethyl, 3-methylthiopropyl, 3-ethylthiopropyl, 3-butylthiopropyl, 3-octylthiopropyl or 4-methylthiobutyl.

Examples of C₂-C₁₈alkyl interrupted by >N—R₀, e.g. one or more >N—R₀, are —CH₂CH₂—N(R₀)—CH₃, —CH₂CH₂—N(R₀)—CH₂CH₃, —CH₂CH₂CH₂—N(R₀)—CH₃ or —CH₂CH₂CH₂—N(R₀)—CH₂CH₃.

Examples of alkenyl containing not more than 18 carbon atoms are allyl, 2-methylallyl, butenyl, hexenyl, undecenyl and octadecenyl. Alkenyls in which the carbon atom in the 1-position is saturated are preferred, and allyl is particularly preferred.

An example of alkynyl containing not more than 18 carbon atoms is 2-butynyl.

Examples of alkoxy containing not more than 18 carbon atoms are methoxy, ethoxy, propoxy, isopropoxy, butoxy, isobutoxy, pentoxy, isopentoxy, hexoxy, heptoxy, octoxy, decyloxy, dodecyloxy, tetradecyloxy, hexadecyloxy and octadecyloxy. C₁-C₁₂Alkoxy, in particular methoxy, propoxy, butoxy and octyloxy, is one of the preferred meanings of R.

Examples of acyl containing not more than 8 carbon atoms are formyl, acetyl, propionyl, butyryl, pentanoyl, hexanoyl, heptanoyl, octanoyl, acryloyl, methacryloyl and benzoyl. C₁-C₈Alkanoyl, C₃-C₈alkenyl and benzoyl are preferred. Acetyl and acryloyl are especially preferred.

Examples of C₁-C₁₈alkanoyloxy are formyloxy, acetyloxy, propionyloxy, butyryloxy, pentanoyloxy, hexanoyloxy, heptanoyloxy and octanoyloxy.

Examples of (C₁-C₁₈alkoxy)carbonyl are methoxycarbonyl, ethoxycarbonyl, propoxycarbonyl, butoxycarbonyl, pentyloxycarbonyl, hexyloxycarbonyl, heptyloxycarbonyl and octyloxycarbonyl.

Examples of C₅-C₁₂cycloalkyl which is unsubstituted or substituted by —OH, C₁-C₄alkyl and/or C₁-C₄alkoxy, e.g. 1, 2 or 3 —OH, C₁-C₄alkyl and/or C₁-C₄alkoxy, are cyclopentyl, methylcyclopentyl, dimethylcyclopentyl, cyclohexyl, methylcyclohexyl, dimethylcyclohexyl, trimethylcyclohexyl, t-butylcyclohexyl, cyclooctyl, cyclodecyl, cyclododecyl and methoxycyclohexyl. Unsubstituted or substituted C₅-C₈cycloalkyl, in particular cyclohexyl, is preferred.

Examples of C₅-C₁₂cycloalkoxy are cyclopentoxy, cyclohexoxy, cycloheptoxy, cyclooctoxy, cyclodecyloxy, cyclododecyloxy and methylcyclohexoxy. C₅-C₈Cycloalkoxy, in particular cyclopentoxy and cyclohexoxy, is preferred.

Examples of phenyl substituted by C₁-C₄alkyl and/or C₁-C₄alkoxy, e.g. 1, 2 or 3 C₁-C₄alkyl and/or C₁-C₄alkoxy, are methylphenyl, dimethylphenyl, trimethylphenyl, t-butylphenyl, di-t-butylphenyl, 3,5-di-t-butyl-4-methylphenyl, methoxyphenyl, ethoxyphenyl and butoxyphenyl.

Examples of C₇-C₁₂phenylalkyl which is unsubstituted or substituted on the phenyl radical by —OH, C₁-C₄alkyl and/or C₁-C₄alkoxy, e.g. 1, 2 or 3 —OH, C₁-C₄alkyl and/or C₁-C₄alkoxy, are benzyl, methylbenzyl, dimethylbenzyl, trimethylbenzyl, t-butylbenzyl, 2-phenylethyl and methoxybenzyl. C₇-C₉phenylalkyl, in particular benzyl, is preferred.

Examples of C₇-C₁₂phenylalkoxy unsubstituted or substituted on the phenyl radical by C₁-C₄alkyl and/or C₁-C₄alkoxy, e.g. 1, 2 or 3 C₁-C₄alkyl and/or C₁-C₄alkoxy, are benzyloxy, methylbenzyloxy, dimethylbenzyloxy, trimethylbenzyloxy, t-butylbenzyloxy, 2-phenylethoxy and methoxybenzyloxy.

C₇-C₉phenylalkoxy, in particular benzyloxy, is preferred.

An example of C₁-C₁₈hydroxyalkoxy is hydroxybutoxy.

An example of C₂-C₁₈alkenyloxy is 2-propenyloxy.

Examples of alkylene containing not more than 12 carbon atoms are methylene, ethylene, propylene, trimethylene, tetramethylene, pentamethylene, hexamethylene, octamethylene, decamethylene and dodecamethylene. One of the preferred meanings of X is C₂-C₁₂alkylene or C₄-C₁₂alkylene, in particular C₂-C₆alkylene or C₄-C₆alkylene.

Examples of alkylene containing not more than 16 carbon atoms and interrupted by —O— or —S—, e.g. one or more —O— or —S—, are 3-oxapentane-1,5-diyl, 4-oxaheptane-1,7-diyl, 3,6-dioxaoctane-1,8-diyl, 4,7-dioxadecane-1,10-diyl, 4,9-dioxadodecane-1,12-diyl, 3,6,9-trioxaundecane-1,11-diyl, 4,7,10-trioxatridecane-1,13-diyl, 3-thiapentane-1,5-diyl, 4-thiaheptane-1,7-diyl, 3,6-dithiaoctane-1,8-diyl, 4,7-dithiadecane-1,10-diyl, 4,9-dithiadodecane-1,12-diyl, 3,6,9-trithiaundecane-1,11-diyl and 4,7,10-trithiatridecane-1,13-diyl.

Examples of alkylene containing not more than 16 carbon atoms and interrupted by >N—R₀′, e.g. one or more >N—R₀′, are —CH₂CH₂—N(R₀)—CH₂CH₂—, —CH₂CH₂CH₂—N(R₀)—CH₂CH₂CH₂— and —CH₂CH₂—CH(CH₃)—N(R₀)—CH₂CH₂CH₂CH₂CH₂CH₂—N(R₀)—CH(CH₃)—CH₂CH₂—.

One of the preferred meanings of X is

-   —CH₂CH₂—CH(CH₃)—N(R₀)—(CH₂)₂₋₆—N(R₀)—CH(CH₃)—CH₂CH₂—.

An example of C₂-C₁₂alkenylene is —CH₂CH═CHCH₂—. C₄-C₁₂alkenylene is preferred.

An example of C₂-C₁₂alkynylene is —CH₂CH₂—C≡C—CH₂CH₂—. C₆-C₁₂alkynylene is preferred.

An example of C₅-C₁₂cycloalkylene is cyclohexylene.

An example of C₁-C₄alkylene-(C₅-C₁₂cycloalkylene)-C₁-C₄alkylene is cyclohexylenedimethylene.

Examples of C₅-C₁₂cycloalkylene-(C₁-C₄alkylene)-C₅-C₁₂cycloalkylene are methylenedicyclohexylene and isopropylidenedicyclohexylene.

An example of phenylene-(C₁-C₄alkylene)-phenylene is methylenediphenylene.

An example of C₁-C₄alkylene-phenylene-C₁-C₄alkylene is phenylenedimethylene.

C₅-C₂₅alkantriyl may be for example a group H₃C—C(CH₂)₃—.

C₄-C₁₈triacyl may be for example an aliphatic C₄-C₁₈triacyl, an aliphatic C₆-C₁₈triacyl substituted by nitrogen, a cycloaliphatic C₆-C₁₈triacyl, an aromatic C₉-C₁₈triacyl or a heterocyclic C₉-C₁₈triacyl.

An aliphatic C₄-C₁₈triacyl is e.g. C₄-C₁₈alkanetrioyl unsubstituted or substituted by OH. Preferred examples are those triacyls derived from methanetricarboxylic acid, 1,1,2-ethanetricarboxylic acid, 1,2,3-propanetricarboxylic acid, citric acid or 1,2,3-butanetricarboxylic acid.

An aliphatic C₆-C₁₈triacyl substituted by nitrogen is e.g.

The group N(CH₂CO—)₃ is especially preferred.

A cycloaliphatic C₆-C₁₈triacyl is e.g.

An aromatic C₉-C₁₈triacyl is e.g. a triacyl derived from 1,2,4-benzenetricarboxylic acid or 1,3,5-benzenetricarboxylic acid.

A heterocyclic C₉-C₁₈triacyl is e.g. a group of the formula

C₅-C₂₀alkantetrayl may be for example C(CH₂)₄—.

A C₆-C₂₂tetraacyl is for example an aliphatic C₆-C₁₈tetraacyl, an aliphatic C₁₀-C₁₈tetraacyl substituted by nitrogen, a cycloaliphatic C₁₀-C₂₂tetraacyl or an aromatic C10-C₁₈tetraacyl.

An aliphatic C₆-C₁₈tetraacyl is e.g. C₆-C₁₈alkanetetraoyl. Preferred examples are those tetraacyls derived from 1,1,3,3-propanetetracarboxylic acid or 1,2,3,4-butanetetracarboxylic acid.

An aliphatic C₁₀-C₁₈tetraacyl substituted by nitrogen is e.g. a group of the formula

A tetraacyl derived from ethylenediaminetetraacetic acid is preferred.

A cycloaliphatic C₁₀-C₂₂tetraacyl is e.g. a cycloalkanetetracarbonyl or a cycloalkenetetracarbonyl such as

An aromatic C₁₀-C₁₈tetraacyl is for example a tetraacyl derived from 1,2,4,5-benzenetetracarboxylic acid.

R is preferably hydrogen, C₁-C₄alkyl, oxyl, —OH, C₃-C₆alkenyl, benzyl, C₁-C₈acyl, C₁-C₁₂alkoxy, C₁-C₁₂hydroxyalkoxy, C₂-C₈alkenyloxy or C₅-C₈cycloalkoxy, in particular hydrogen, methyl, allyl, acetyl, methoxy, propoxy, butoxy, octyloxy, hydroxybutoxy, 2-propenyloxy or cyclohexyloxy.

n is preferably 2.

q is preferably an integer from 2 to 6.

Compounds which are of interest are those wherein

-   when n is 1, X is C₂-C₁₂alkyl, C₂-C₁₂hydroxyalkyl, C₂-C₁₂alkyl     interrupted by oxygen or >N—R₀ with R₀ being as defined below;     C₂-C₁₈alkenyl, C₅-C₈cycloalkyl unsubstituted or substituted by     C₁-C₄alkyl; or benzyl unsubstituted or substituted on the phenyl     radical by —OH and/or C₁-C₄alkyl; or X is one of the groups of the     formulae (II-a) to (II-m); -   Y₁, Y₂, Y₅, Y₆, Y₇ and Y₉ are a direct bond, C₁-C₆alkylene,     cyclohexylene or phenylene; -   Y₃, Y₄, Y₈, Y₁₀, Y₁₁ and Y₁₂ are C₂-C₆alkylene, cyclohexylene or     phenylene; -   R₁, R₂, R₃, R₄, R₅, R₆, R₇ and R₁₃ are hydrogen, C₁-C₁₂alkyl,     C₂-C₁₂alkyl interrupted by oxygen or >N—R₀ with R₀ being as defined     below; C₂-C₁₈alkenyl, C₅-C₈cycloalkyl unsubstituted or substituted     by C₁-C₄alkyl; phenyl unsubstituted or substituted by C₁-C₄alkyl; or     benzyl unsubstituted or substituted on the phenyl radical by     C₁-C₄alkyl; -   Z₁, Z₂ and Z₃ are independently of one another —O— or >N—R₁₆; -   R₀, R₈, R₉, R₁₀, R₁₁, R₁₂, R₁₄, R₁₅ and R₁₆ are independently of one     another hydrogen, C₁-C₁₂alkyl, C₃-C₁₈alkenyl, C₅-C₈cycloalkyl which     is unsubstituted or substituted by C₁-C₄alkyl; or benzyl     unsubstituted or substituted on the phenyl radical by C₁-C₄alkyl; -   with the proviso that the formula (II-b) is different from     ethoxycarbonyl; -   when n is 2, X is C₂-C₆alkylene, C₂-C₁₆alkylene interrupted by     oxygen or >N—R₀′ with R₀′ being as defined below; C₂-C₆alkenylene,     cyclohexylene, cyclohexylene-(C₁-C₄alkylene)-cyclohexylene,     C₁-C₄alkylene-cyclohexylene-C₁-C₄alkylene or     C₁-C₄alkylene-phenylene-C₁-C₄alkylene, or X is one of the groups of     the formulae (III-a) to (III-j); -   Y₁′, Y₁″, Y₂′, Y₂″, Y₅′, Y₅″, Y₆′, Y₆″, Y₇′ and Y₇″ are     independently of one another a direct bond, C₁-C₆alkylene,     cyclohexylene or phenylene; -   Y₃′, Y₃″, Y₄′, Y₄″, Y₈′, Y₈″, Y₁₁′, Y₁₁″, Y₁₂′ and Y₁₂″ are     independently of one another C₂-C₆alkylene, cyclohexylene or     phenylene; -   A₁, A₂, A₃, A₄, A₅, A₆, A₇, A₈ and A₉ are C₂-C₆alkylene,     C₂-C₆alkylene interrupted by oxygen or >N—R₀′ with R₀′ being as     defined below, C₂-C₆alkenylene, cyclohexylene,     cyclohexylene-(C₁-C₄alkylene)-cyclohexylene,     C₁-C₄alkylene-cyclohexylene-C₁-C₄alkylene or     C₁-C₄alkylene-phenylene-C₁-C₄alkylene; and A₁ and A₅ are     additionally a direct bond; -   Z₁′, Z₂′ and Z₃′ are independently of one another —O— or >N—R₁₆′;     and -   R₀′, R₁₄′ and R₁₆′ are independently of one another hydrogen,     C₁-C₁₂alkyl, C₃-C₁₈alkenyl, C₅-C₈cycloalkyl which is unsubstituted     or substituted by C₁-C₄alkyl; or benzyl which is unsubstituted or     substituted on the phenyl radical by C₁-C₄alkyl; -   when n is 3, X is C₅-C₁₀alkantriyl, an aliphatic C₄-C₁₈triacyl, an     aliphatic C₆-C₁₈triacyl substituted by nitrogen; a cycloaliphatic     C₆-C₁₈triacyl, an aromatic C₉-C₁₈triacyl, a heterocyclic     C₉-C₁₈triacyl or a group of the formula (IV); -   Y₁₃′, Y₁₃″ and Y₁₃′″ are independently of one another C₂-C₆alkylene,     cyclohexylene or phenylene; -   Z₁″, Z₂″ and Z₃″ are independently of one another —O— or >N—R₁₆″;     and -   R₁₆″ is hydrogen, C₁-C₁₂alkyl, C₃-C₁₈alkenyl, C₅-C₈cycloalkyl which     is unsubstituted or substituted by C₁-C₄alkyl; or benzyl which is     unsubstituted or substituted on the phenyl radical by C₁-C₄alkyl;     and -   when n is 4, X is C₅-C₁₀alkantetrayl, an aliphatic C₆-C₁₈tetraacyl,     an aliphatic C₁₀-C₁₈tetraacyl substituted by nitrogen, a     cycloaliphatic C₁₀-C₂₂tetraacyl, an aromatic C₁₀-C₁₈tetraacyl or a     group of the formula (V); -   Y₁₄′ and Y₁₄″ are independently of one another C₂-C₆alkylene,     cyclohexylene or phenylene; -   Z₁′″, Z₂′″, M and T are independently of one another —O— or     >N—R₁₆′″, and M and T are additionally —S—; -   R₁₆′″ is hydrogen, C₁-C₁₂alkyl, C₃-C₁₈alkenyl, C₅-C₈cycloalkyl which     is unsubstituted or substituted by C₁-C₄alkyl; or benzyl which is     unsubstituted or substituted on the phenyl radical by C₁-C₄alkyl;     and -   q is an integer from 2 to 12.

Compounds which are of particular interest are those wherein

-   when n is 1, X is C₂-C₆alkyl, C₂-C₆hydroxyalkyl, C₂-C₆alkyl     interrupted by oxygen; allyl, cyclohexyl, benzyl or one of the     groups of the formulae (II-a) to (II-l); -   Y₁, Y₂, Y₅, Y₆, Y₇ and Y₉ are a direct bond, C₁-C₆alkylene,     cyclohexylene or phenylene; -   Y₃, Y₄, Y₈, Y₁₀, Y₁₁ and Y₁₂ are C₂-C₆alkylene, cyclohexylene or     phenylene; -   R₁, R₂, R₃, R₄, R₅, R₆, R₇ and R₁₃ are hydrogen, C₁-C₈alkyl,     C₂-C₆alkyl interrupted by oxygen; allyl, cyclohexyl, phenyl or     benzyl; -   Z₁, Z₂ and Z₃ are independently of one another —O— or >N—R₁₆; -   R₀, R₈, R₉, R₁₀, R₁₁, R₁₂, R₁₄, R₁₅ and R₁₆ are independently of one     another hydrogen, C₁-C₆alkyl, allyl, cyclohexyl or benzyl; -   with the proviso that the formula (II-b) is different from     ethoxycarbonyl; -   when n is 2, X is C₂-C₆alkylene, C₂-C₁₄alkylene interrupted by     oxygen or >N—R₀′; cyclohexylene or one of the groups of the formulae     (III-a) to (III-j); -   Y₁′, Y₁″, Y₂′, Y₂″, Y₅′, Y₅″, Y₆′, Y₆″, Y₇′ and Y₇″ are     independently of one another a direct bond, C₁-C₆alkylene,     cyclohexylene or phenylene; -   Y₃′, Y₃″, Y₄′, Y₄″, Y₈′, Y₈″, Y₁₁′, Y₁₁″, Y₁₂′ and Y₁₂″ are     independently of one another C₂-C₆alkylene, cyclohexylene or     phenylene; -   A₁, A₂, A₃, A₄, A₅, A₆, A₇, A₈ and A₉ are C₂-C₆alkylene,     C₂-C₆alkylene interrupted by oxygen; cyclohexylene or phenylene; and     A₁ and A₅ are additionally a direct bond; -   Z₁′, Z₂′ and Z₃′ are independently of one another —O— or >N—R₁₆′;     and -   R₀′, R₁₄′ and R₁₆′ are independently of one another hydrogen,     C₁-C₆alkyl, allyl, cyclohexyl or benzyl: -   when n is 3, X is a group of the formula (IV); -   Y₁₃′, Y₁₃″ and Y₁₃′″ are independently of one another C₂-C₆alkylene,     cyclohexylene or phenylene; -   Z₁″, Z₂″ and Z₃″ are independently of one another —O— or >N—R₁₆″;     and -   R₁₆″ is hydrogen, C₁-C₆alkyl, allyl, cyclohexyl or benzyl; and -   when n is 4, X is a group of the formula (V); -   Y₁₄′ and Y₁₄″ are independently of one another C₂-C₆alkylene,     cyclohexylene or phenylene; -   Z₁′″, Z₂′″, M and T are independently of one another —O— or     >N—R₁₆′″; -   R₁₆′″ is hydrogen, C₁-C₆alkyl, allyl, cyclohexyl or benzyl; and -   q is an integer from 2 to 12.

Compounds which are further of interest are those wherein

-   when n is 2, X is C₂-C₆alkylene or C₂-C₁₄alkylene interrupted by     oxygen or >N—R₀′; or X is a group of the formula (III-a), (III-b) or     (III-j).

Preferred compounds are also those wherein

-   G₁, G₂, G₃ and G₄ are methyl; -   R is hydrogen, methyl, allyl, acetyl, propoxy or 2-propenyloxy; -   when n is 1, X is a group of the formula (II-a) or (II-l); -   Y₁ is a direct bond or C₁-C₆alkylene; -   R₁ is C₁-C₈alkyl; -   Z₁, Z₂ and Z₃ are >N—R₁₆; -   R₁₄, R₁₅ and R₁₆ are independently of one another hydrogen or     C₁-C₆alkyl; and -   Y₁₂ is C₂-C₆alkylene; -   when n is 2, X is C₂-C₆alkylene, C₂-C₁₄alkylene interrupted by     2>N—H; or a group of the formula (III-b) or (III-j); -   Y₂′, Y₂″, Y₁₂′ and Y₁₂″ are independently of one another     C₁-C₆alkylene; -   A₂ is C₂-C₆alkylene; -   Z₁′, Z₂′ and Z₃′ are independently of one another >N—R₁₆′; and -   R₁₄′ and R₁₆′ are independently of one another hydrogen or     C₁-C₆alkyl; -   when n is 3, X is a group of the formula (IV); -   Y₁₃′, Y₁₃″ and Y₁₃′″ are independently of one another C₂-C₆alkylene; -   Z₁″, Z₂″ and Z₃″ are a group >N—H; and -   when n is 4, X is a group of the formula (V); -   Y₁₄′ and Y₁₄″ are independently of one another C₂-C₆alkylene; -   Z₁′″, Z₂′″, M and T are a group >N—H; and -   q is an integer from 2 to 6.

A particularly preferred embodiment of the present invention relates to compounds wherein

-   G₁, G₂, G₃ and G₄ are methyl; -   R is hydrogen, methyl, allyl, acetyl, propoxy or 2-propenyloxy; -   n is 2; -   X is C₂-C₆alkylene or a group of the formula (III-b); -   Y₂′ and Y₂″ are independently of one another C₁-C₆alkylene; and -   A₂ is C₂-C₆alkylene.

A further particularly preferred embodiment of the present invention relates to compounds wherein

-   G₁, G₂, G₃ and G₄ are methyl; -   R is hydrogen, methyl or allyl; -   n is 1; -   X is C₂-C₆alkyl, C₂-C₆hydroxyalkyl or a group of the formula (II-b)     or (II-m); -   Y₂ is C₁-C₆alkylene; and -   R₂ is hydrogen.

Examples of compounds of the formula (I) are

The compounds of the formulae (1-a), (1-b), (1-c), (1-d), (4-0-a), (4-0-b), (4-0-c), (4-0-d), (4-0-e), (8-a) and (8-b) are particularly preferred and the compounds of the formulae (4-0-c) and (1-b) are of special interest.

The compounds of the formula (I) can be prepared, for example, according to the following reaction scheme.

wherein G₁, G₂, G₃, G₄, X and n are as defined above and Hal means e.g. Br, Cl or J, preferably Cl.

The reaction can be carried out without isolation of the intermediate compounds in the presence of an organic solvent. Suitable organic solvents are for example acetone and an alcohol such as methanol or ethanol. The ratio of the reactants is preferably stoichiometric but it is also possible to use thioimidazolidinone in an excess of up to 10%. The base K₂CO₃ can be applied in an excess of up to 50%, preferably 15%. The reaction temperature depends on the solvent. Normally, the reaction is carried out at the boiling point of the solvent. Instead of K₂CO₃, also other bases can be used. Examples are Na₂CO₃, Na—O—CH₃, K—O—CH₃ and K—O—C(CH₃)₃. When Na₂CO₃ is used as base, Hal is preferably Br.

The substitution of the nitrogen >N—H of the final product (that means the introduction of the radical R different from hydrogen) can be carried out according to known processes.

The thioimidazolidinone starting material is known and can be prepared in analogy to known processes. When G₁, G₂, G₃ and G₄ are methyl, it can also be prepared as shown in SCHEME 2 below.

This reaction is described in detail in Example 1A.

The intermediate 2,2,5,5-tetramethylimidazolidin-4-thione may also be prepared according to the following reaction scheme. When desired, the nitrogen atom in the 1-position can be substituted by the radicals listed above for R in analogy to known methods.

Acetone cyanohydrin is reacted at room temperature with acetone and with an aqueous solution of ammonium chloride and Na₂S. The reaction is described in detail in Example 1-I-A. The desired intermediate is recovered by filtration as a white powder.

A further method for the preparation of the compounds of the formula (I) is shown in SCHEME 4.

wherein the radicals G₁, G₂, G₃, G₄, R and X and the variable n are as defined above, and HAL is an appropriate halogen, preferably chlorine.

The starting material of the formula (S-1) is conveniently reacted with an appropriate halogen derivative of the formula (S-2) in an inert organic solvent which has for example a boiling temperature of 120-160° C., preferably 130-150° C., in particular 130-140° C. The reaction is carried out at reflux temperature (that means the boiling temperature of the solvent). A particular preferred solvent is xylene. The use of a base is not necessary during the reaction. The ratio of the starting materials (S-1):(S-2) is preferably stoichiometric but an excess of e.g. up to 30 mol % of the compound of the formula (S-1) can be applied. After the end of the reaction, the halogen salt of the desired product precipitates. In order to obtain the final product, the salt can be treated with for example an aqueous NaOH solution. A detailed example of this procedure is given in Example 1-I-b.

When R in the above SCHEME 4 is hydrogen, it is also possible to replace this hydrogen atom by the other meanings given for R after the end of the reaction according to known methods.

A further embodiment of the present invention is a method for the preparation of the compounds of the formula (I), which comprises reacting a compound of the formula (S-1)

with a compound of the formula (S-2) [HAL

_(n)X  (S-2) in an inert organic solvent in the absence of a base; the proviso being not applied to the radical X.

The compounds of this invention are very effective in improving the light, heat and oxidation resistance of organic materials.

Examples of such organic materials are:

1. Polymers of monoolefins and diolefins, for example polypropylene, polyisobutylene, polybut-1-ene, poly-4-methylpent-1-ene, polyisoprene or polybutadiene, as well as polymers of cycloolefins, for instance of cyclopentene or norbornene, polyethylene (which optionally can be crosslinked), for example high density polyethylene (HDPE), high density and high molecular weight polyethylene (HDPE-HMW), high density and ultrahigh molecular weight polyethylene (HDPE-UHMW), medium density polyethylene (MDPE), low density polyethylene (LDPE), linear low density polyethylene (LLDPE), (VLDPE) and (ULDPE).

Polyolefins, i.e. the polymers of monoolefins exemplified in the preceding paragraph, preferably polyethylene and polypropylene, can be prepared by different, and especially by the following, methods:

-   -   a) radical polymerisation (normally under high pressure and at         elevated temperature).     -   b) catalytic polymerisation using a catalyst that normally         contains one or more than one metal of groups IVb, Vb, VIb or         VIII of the Periodic Table. These metals usually have one or         more than one ligand, typically oxides, halides, alcoholates,         esters, ethers, amines, alkyls, alkenyls and/or aryls that may         be either π- or σ-coordinated. These metal complexes may be in         the free form or fixed on substrates, typically on activated         magnesium chloride, titanium(III) chloride, alumina or silicon         oxide. These catalysts may be soluble or insoluble in the         polymerisation medium. The catalysts can be used by themselves         in the polymerisation or further activators may be used,         typically metal alkyls, metal hydrides, metal alkyl halides,         metal alkyl oxides or metal alkyloxanes, said metals being         elements of groups Ia, IIa and/or IIIa of the Periodic Table.         The activators may be modified conveniently with further ester,         ether, amine or silyl ether groups. These catalyst systems are         usually termed Phillips, Standard Oil Indiana, Ziegler (-Natta),         TNZ (DuPont), metallocene or single site catalysts (SSC).

2. Mixtures of the polymers mentioned under 1), for example mixtures of polypropylene with polyisobutylene, polypropylene with polyethylene (for example PP/HDPE, PP/LDPE) and mixtures of different types of polyethylene (for example LDPE/HDPE).

3. Copolymers of monoolefins and diolefins with each other or with other vinyl monomers, for example ethylene/propylene copolymers, linear low density polyethylene (LLDPE) and mixtures thereof with low density polyethylene (LDPE), propylene/but-1-ene copolymers, propylene/isobutylene copolymers, ethylene/but-1-ene copolymers, ethylene/hexene copolymers, ethylene/methylpentene copolymers, ethylene/heptene copolymers, ethylene/octene copolymers, propylene/butadiene copolymers, isobutylene/isoprene copolymers, ethylene/alkyl acrylate copolymers, ethylene/alkyl methacrylate copolymers, ethylene/vinyl acetate copolymers and their copolymers with carbon monoxide or ethylene/acrylic acid copolymers and their salts (ionomers) as well as terpolymers of ethylene with propylene and a diene such as hexadiene; dicyclopentadiene or ethylidene-norbornene; and mixtures of such copolymers with one another and with polymers mentioned in 1) above, for example polypropylene/ethylene-propylene copolymers, LDPE/ethylene-vinyl acetate copolymers (EVA), LDPE/ethylene-acrylic acid copolymers (EAA), LLDPE/EVA, LLDPE/EAA and alternating or random polyalkylene/carbon monoxide copolymers and mixtures thereof with other polymers, for example polyamides.

4. Hydrocarbon resins (for example C₅-C₉) including hydrogenated modifications thereof (e.g. tackifiers) and mixtures of polyalkylenes and starch.

5. Polystyrene, poly(p-methylstyrene), poly(α-methylstyrene).

6. Copolymers of styrene or α-methylstyrene with dienes or acrylic derivatives, for example styrene/butadiene, styrene/acrylonitrile, styrene/alkyl methacrylate, styrene/butadiene/alkyl acrylate, styrene/butadiene/alkyl methacrylate, styrene/maleic anhydride, styrene/acrylonitrile/methyl acrylate; mixtures of high impact strength of styrene copolymers and another polymer, for example a polyacrylate, a diene polymer or an ethylene/propylene/diene terpolymer; and block copolymers of styrene such as styrene/butadiene/styrene, styrene/isoprene/styrene, styrene/ethylene/butylene/styrene or styrene/ethylene/propylene/styrene.

7. Graft copolymers of styrene or α-methylstyrene, for example styrene on polybutadiene, styrene on polybutadiene-styrene or polybutadiene-acrylonitrile copolymers; styrene and acrylonitrile (or methacrylonitrile) on polybutadiene; styrene, acrylonitrile and methyl methacrylate on polybutadiene; styrene and maleic anhydride on polybutadiene; styrene, acrylonitrile and maleic anhydride or maleimide on polybutadiene; styrene and maleimide on polybutadiene; styrene and alkyl acrylates or methacrylates on polybutadiene; styrene and acrylonitrile on ethylene/propylene/diene terpolymers; styrene and acrylonitrile on polyalkyl acrylates or polyalkyl methacrylates, styrene and acrylonitrile on acrylate/butadiene copolymers, as well as mixtures thereof with the copolymers listed under 6), for example the copolymer mixtures known as ABS, MBS, ASA or AES polymers.

8. Halogen-containing polymers such as polychloroprene, chlorinated rubbers, chlorinated and brominated copolymer of isobutylene-isoprene (halobutyl rubber), chlorinated or sulfochlorinated polyethylene, copolymers of ethylene and chlorinated ethylene, epichlorohydrin homo- and copolymers, especially polymers of halogen-containing vinyl compounds, for example polyvinyl chloride, polyvinylidene chloride, polyvinyl fluoride, polyvinylidene fluoride, as well as copolymers thereof such as vinyl chloride/vinylidene chloride, vinyl chloride/vinyl acetate or vinylidene chloride/vinyl acetate copolymers.

9. Polymers derived from α,β-unsaturated acids and derivatives thereof such as polyacrylates and polymethacrylates; polymethyl methacrylates, polyacrylamides and polyacrylonitriles, impact-modified with butyl acrylate.

10. Copolymers of the monomers mentioned under 9) with each other or with other unsaturated monomers, for example acrylonitrile/butadiene copolymers, acrylonitrile/alkyl acrylate copolymers, acrylonitrile/alkoxyalkyl acrylate or acrylonitrile/vinyl halide copolymers or acrylonitrile/alkyl methacrylate/butadiene terpolymers.

11. Polymers derived from unsaturated alcohols and amines or the acyl derivatives or acetals thereof, for example polyvinyl alcohol, polyvinyl acetate, polyvinyl stearate, polyvinyl benzoate, polyvinyl maleate, polyvinyl butyral, polyallyl phthalate or polyallyl melamine; as well as their copolymers with olefins mentioned in 1) above.

12. Homopolymers and copolymers of cyclic ethers such as polyalkylene glycols, polyethylene oxide, polypropylene oxide or copolymers thereof with bisglycidyl ethers.

13. Polyacetals such as polyoxymethylene and those polyoxymethylenes which contain ethylene oxide as a comonomer; polyacetals modified with thermoplastic polyurethanes, acrylates or MBS.

14. Polyphenylene oxides and sulfides, and mixtures of polyphenylene oxides with styrene polymers or polyamides.

15. Polyurethanes derived from hydroxyl-terminated polyethers, polyesters or polybutadienes on the one hand and aliphatic or aromatic polyisocyanates on the other, as well as precursors thereof.

16. Polyamides and copolyamides derived from diamines and dicarboxylic acids and/or from aminocarboxylic acids or the corresponding lactams, for example polyamide 4, polyamide 6, polyamide 6/6, 6/10, 6/9, 6/12, 4/6, 12/12, polyamide 11, polyamide 12, aromatic polyamides starting from m-xylene diamine and adipic acid; polyamides prepared from hexamethylenediamine and isophthalic or/and terephthalic acid and with or without an elastomer as modifier, for example poly-2,4,4,-trimethylhexamethylene terephthalamide or polymphenylene isophthalamide; and also block copolymers of the aforementioned polyamides with polyolefins, olefin copolymers, ionomers or chemically bonded or grafted elastomers; or with polyethers, e.g. with polyethylene glycol, polypropylene glycol or polytetramethylene glycol; as well as polyamides or copolyamides modified with EPDM or ABS; and polyamides condensed during processing (RIM polyamide systems).

17. Polyureas, polyimides, polyamide-imides, polyetherimids, polyesterimids, polyhydantoins and polybenzimidazoles.

18. Polyesters derived from dicarboxylic acids and diols and/or from hydroxycarboxylic acids or the corresponding lactones, for example polyethylene terephthalate, polybutylene terephthalate, poly-1,4-dimethylolcyclohexane terephthalate, polyalkylene naphthalate (PAN) and polyhydroxybenzoates, as well as block copolyether esters derived from hydroxyl-terminated polyethers; and also polyesters modified with polycarbonates or MBS.

19. Polycarbonates and polyester carbonates.

20. Polysulfones, polyether sulfones and polyether ketones.

21. Crosslinked polymers derived from aidehydes on the one hand and phenols, ureas and melamines on the other hand, such as phenol/formaldehyde resins, urea/formaldehyde resins and melamine/formaldehyde resins.

22. Drying and non-drying alkyd resins.

23 Unsaturated polyester resins derived from copolyesters of saturated and unsaturated dicarboxylic acids with polyhydric alcohols and vinyl compounds as crosslinking agents, and also halogen-containing modifications thereof of low flammability.

24. Crosslinkable acrylic resins derived from substituted acrylates, for example epoxy acrylates, urethane acrylates or polyester acrylates.

25. Alkyd resins, polyester resins and acrylate resins crosslinked with melamine resins, urea resins, isocyanates, isocyanurates, polyisocyanates or epoxy resins.

26. Crosslinked epoxy resins derived from aliphatic, cycloaliphatic, heterocyclic or aromatic glycidyl compounds, e.g. products of diglycidyl ethers of bisphenol A and bisphenol F, which are crosslinked with customary hardeners such as anhydrides or amines, with or without accelerators.

27. Natural polymers such as cellulose, rubber, gelatin and chemically modified homologous derivatives thereof, for example cellulose acetates, cellulose propionates and cellulose butyrates, or the cellulose ethers such as methyl cellulose; as well as rosins and their derivatives.

28. Blends of the aforementioned polymers (polyblends), for example PP/EPDM, PP/SEBS, PP/SEPS, PE/SEBS, PE/SEPS, Polyamide/EPDM or ABS, PVC/EVA, PVC/ABS, PVC/MBS, PC/ABS, PBTP/ABS, PC/ASA, PC/PBT, PVC/CPE, PVC/acrylates, POM/thermoplastic PUR, PC/thermoplastic PUR, POM/acrylate, POM/MBS, PPO/HIPS, PPO/PA 6.6 and copolymers, PA/HDPE, PA/PP, PA/PPO, PA/SEBS, PBT/PC/ABS or PBT/PET/PC.

Blends of aforementioned polymers, particularly of polyolefin polymers, with vulcanized elastomers (partially or fully vulcanized), for example PP/EPDM, PP/NBR, PP/Natural Rubber, PP/Halobutyl. The elastomer component can be vulcanized by means of sulfur based systems, peroxides, phenolic resins, silanes or other systems.

29. Naturally occurring and synthetic organic materials which are pure monomeric compounds or mixtures of such compounds, for example mineral oils, animal and vegetable fats, oil and waxes, or oils, fats and waxes based on synthetic esters (e.g. phthalates, adipates, phosphates or trimellitates) and also mixtures of synthetic esters with mineral oils in any weight ratios, typically those used as spinning compositions, as well as aqueous emulsions of such materials.

30. Aqueous emulsions of natural or synthetic rubber, e.g. natural latex, latices of styrene/butadiene and carboxylated styrene/butadiene copolymers, styrene/acrylonitrile and carboxylated styrene/acrylonitrile copolymers, polyvinylacetate copolymers, acrylates and copolymers.

The invention thus also relates to a composition comprising an organic material susceptible to degradation induced by light, heat or oxidation and at least one compound of the formula (IA)

wherein

-   G₁, G₂, G₃ and G₄ are independently of one another C₁-C₁₈alkyl or     C₅-C₁₂cycloalkyl or the radicals G₁ and G₂ and the radicals G₃ and     G₄ form independently of one another, together with the carbon atom     they are attached to, C₅-C₁₂cycloalkyl; -   R is hydrogen, C₁-C₁₈alkyl, oxyl, —OH, —CH₂CN, C₃-C₆alkenyl,     C₃-C₈alkynyl, C₇-C₁₂phenylalkyl unsubstituted or substituted on the     phenyl radical by C₁-C₄alkyl and/or C₁-C₄alkoxy; C₁-C₈acyl,     C₁-C₁₈alkoxy, C₁-C₁₈hydroxyalkoxy, C₂-C₁₈alkenyloxy,     C₅-C₁₂cycloalkoxy, C₇-C₁₂phenylalkoxy unsubstituted or substituted     on the phenyl radical by C₁-C₄alkyl and/or C₁-C₄alkoxy;     C₁-C₁₈alkanoyloxy, (C₁-C₁₈alkoxy)carbonyl, glycidyl or a group     —CH₂CH(OH)(G) with G being hydrogen, methyl or phenyl; -   n is 1, 2, 3 or 4; and -   X is an organic radical of a valency equal to n; and -   when n is 2, 3 or 4, each of the radicals G₁, G₂, G₃, G₄ and R can     have the same or a different meaning in the units of the formula     with the proviso that a photographic material containing a compound     of the formula     is disclaimed.

The organic material may be for example different from a recording material, in particular a photographic material.

The organic material is preferably a synthetic polymer, more particularly one selected from the aforementioned groups. The synthetic polymer is for example a thermoplastic polyolefin (TPO), a thermoplastic elastomer (TPE) or a thermoplastic vulcanizate (TPV).

Polyolefins are preferred. Thermoplastic polyolefins (TPO) or acrylonitrile-butadiene-styrene (ABS) are also preferred.

The compounds of the formula (IA) are further useful as corrosion inhibitors and also as light stabilizers for coatings. Thus, a further embodiment of the present invention relates to a coating containing a compound of the formula (IA). Suitable coatings are for example described in U.S. Pat. No. 6,117,997, column 26, line 55 to column 32, line 21.

Pigmented vulcanized rubbers or pigmented thermoplastic elastomers containing a compound of the formula (IA) are a particularly preferred embodiment of this invention. A pigmented (non black) rubber vulcanizate contains for example elastomers, vulcanizing agents, accelerators, accelerator activators, age-resistors, fillers/pigments, softeners and some further miscellaneous ingredients.

Examples of elastomers are polyisoprene or polybutadiene; copolymers of monoolefins and diolefins with each other or with other vinyl monomers, e.g. ethylene/octene copolymers, propylene/butadiene copolymers, isobutylene/isoprene copolymers, ethylene/alkyl acrylate copolymers or ethylene/alkyl methacrylate copolymers; terpolymers of ethylene with propylene and a diene such as hexadiene, dicyclopentadiene or ethylidene-norbornene; and mixtures of such copolymers with one another and with polymers mentioned above in 1); copolymers of styrene or α-methylstyrene with dienes or acrylic derivatives, for example styrene/butadiene, styrene/acrylonitrile, styrene/alkyl methacrylate, styrene/butadiene/alkyl acrylate or styrene/butadiene/alkyl methacrylate; block copolymers of styrene such as styrene/butadiene/styrene, styrene/isoprene/styrene, styrene/ethylene/butylene/styrene or styrene/ethylene/propylene/styrene; halogen-containing polymers such as polychloroprene, chlorinated rubbers, chlorinated and brominated copolymer of isobutylene-isoprene (halobutyl rubber) or chlorinated or sulfochlorinated polyethylene; copolymers of the monomers mentioned above under 9) with each other or with other unsaturated monomers, for example acrylonitrile/butadiene copolymers; polyblends such as PP/EPDM, polyamide/EPDM or ABS; or aqueous emulsions of natural or synthetic rubber, e.g. natural latex or latices of carboxylated styrene/butadiene copolymers.

Vulcanizing agents are chemicals that are required to crosslink the rubber chains into the three-dimensional network which gives the desired physical properties in the final product. The most common agent used is sulfur and sulfur-bearing chemicals (sulfur donors). Examples of agents which are used for non-sulfur vulcanization are metal oxides, di- or polyfunctional compounds and peroxides.

Accelerators are generally needed for sulfur-crosslinking. These chemicals reduce the time required for vulcanization and improve the properties of the vulcanizate. Accelerators belong mainly to the following chemical groups: amines (e.g. hexamethylene tetramins), guanidines (e.g. diphenyl guanidine), thioureas, thiazoles, thiurams, sulfenamides or dithiocarbamates.

Accelerator activators are components used to increase the vulcanization rate by activating the accelerator so that it performs more effectively. Accelerator activators are for example inorganic compounds (mainly metal oxides) such as zinc oxide, red lead, magnesium oxide or alkali carbonates. The most common accelerator activator is zinc oxide. Further, accelerator activators can also be organic acids (normally used in combination with metal oxides) such as high molecular weight monobasic acids or mixtures thereof. Examples are stearic acid, oleic acid, lauric acid, palmitic acid and myristic acid.

Age-resisters are usually selected from the below-mentioned list of conventional additives.

Fillers may either reinforce, extend, dilute, or impart certain properties to rubbers. Carbon black is normally used for black formulations. For non-black colored formulations, fillers and pigments from the following classes of mineral fillers can be used:

Pyrogenic or precipitated silica, calcium silicate, calcium carbonate, china clay and hard clay.

Examples of further miscellaneous ingredients are:

-   -   a) colorants or pigments such as titanium dioxide, zinc oxide,         zinc sulfide, iron oxide, Microlen (RTM) Yellow 3G, Microlen         (RTM) DPP Red BP, Microlen (RTM) Green GFN, Ciba (RTM) IRGACOLOR         (RTM) Yellow 2GLMA, Ciba (RTM) IRGACOLOR (RTM) Yellow 2GTM, Ciba         (RTM) CROMOPHTAL (RTM) Yellow 8GN, Ciba (RTM) IRGAZIN (RTM)         Yellow 2GLTE, Ciba (RTM) IRGALITE (RTM) Yellow WGP, Ciba (RTM)         CROMOPHTAL (RTM) Yellow 3G, Ciba (RTM) IRGALITE (RTM) Yellow         WSR, Ciba (RTM) IRGALITE (RTM) Yellow BAWP, Ciba (RTM)         CROMOPHTAL (RTM) Yellow GR, Ciba (RTM) CROMOPHTAL (RTM) Yellow         GT-AD, Ciba (RTM) CROMOPHTAL (RTM) Yellow HRP, Ciba (RTM)         CROMOPHTAL (RTM) Yellow 2RF, Ciba (RTM) CROMOPHTAL (RTM) Yellow         2RLTS, Ciba (RTM) CROMOPHTAL (RTM) Yellow 2RLP, Ciba (RTM)         IRGAZIN (RTM) Yellow 3RLTN, Ciba (RTM) CROMOPHTAL (RTM) Orange         2G, Ciba (RTM) CROMOPHTAL (RTM) DPP Orange TRP, Ciba (RTM)         CROMOPHTAL (RTM) Orange GP, Ciba (RTM) IRGALITE (RTM) Orange         F2G, Ciba (RTM) IRGAZIN (RTM) DPP Orange RA, Ciba (RTM)         CROMOPHTAL (RTM) Brown 5R, Ciba (RTM) CROMOPHTAL (RTM) Scarlet         RN, Ciba (RTM) IRGALITE (RTM) Red LCB, Ciba (RTM) IRGALITE (RTM)         Red 2BY, Ciba (RTM) CROMOPHTAL (RTM) DPP Flame Red EP, Ciba         (RTM) CROMOPHTAL (RTM) Red G, Ciba (RTM) CROMOPHTAL (RTM) DPP         Red BOC, Ciba (RTM) IRGAZIN (RTM) DPP Red BO, Ciba (RTM)         CROMOPHTAL (RTM) DPP Red BP, Ciba (RTM) CROMOPHTAL (RTM) Red         2030, Ciba (RTM) IRGAZIN (RTM) DPP Red BTR, Ciba (RTM)         CROMOPHTAL (RTM) Red BRN, Ciba (RTM) CROMOPHTAL (RTM) Red BN,         Ciba (RTM) IRGALITE (RTM) Red 2BSP, Ciba (RTM) IRGAZIN (RTM) DPP         Rubine TR, Ciba (RTM) CROMOPHTAL (RTM) Red A₃B, Ciba (RTM)         CROMOPHTAL (RTM) Red 2B, Ciba (RTM) CROMOPHTAL (RTM) Red 2020,         Ciba (RTM) CINQUASIA (RTM) Red Y RT-759-D, Ciba (RTM) IRGALITE         (RTM) Red 2BP, Ciba (RTM) CINQUASIA (RTM) Red B RT-790-D, Ciba         (RTM) IRGALITE (RTM) Rubine 4BP, Ciba (RTM) CINQUASIA (RTM) Red         B RT-195-D, Ciba (RTM) CINQUASIA (RTM) Magenta RT-235-D, Ciba         (RTM) CINQUASIA (RTM) Violet R RT-891-D, Ciba (RTM) CROMOPHTAL         (RTM) Violet B, Ciba (RTM) CROMOPHTAL (RTM) Violet GT, Ciba         (RTM) CROMOPHTAL (RTM) Blue A₃R, Ciba (RTM) IRGALITE (RTM) Blue         BLPO, Ciba (RTM) IRGALITE (RTM) Blue BSP, Ciba (RTM) CROMOPHTAL         (RTM) Blue 4GNP, Ciba (RTM) IRGALITE (RTM) Blue GBP, Ciba (RTM)         IRGALITE (RTM) Green GFNP;     -   b) blowing agents, c) flame retardants, d) retarders, e)         odorants, and f) abrasives.

In pigmented vulcanized rubbers or pigmented thermoplastic elastomers, the compound of the formula (IA) is preferably applied together with an UV absorber, in particular one of those listed in group 2 of the list of conventional additives further below. The combination of one of the compounds of Examples 1 to 11 of this invention with ®TINUVIN 213 which is the transesterification product of 2-[3′-tert-butyl-5′-(2-methoxycarbonylethyl)-2′-hydroxyphenyl]-2H-benzotriazole with polyethylene glycol 300 is particularly preferred.

A further embodiment of this invention is a method for stabilizing an organic material against degradation induced by light, heat or oxidation, which comprises incorporating into said organic material at least one compound of the formula (IA); with the proviso that the compound of the formula (IA) is different from

when the organic material is a photographic material.

The compounds of this invention can be used in various proportions depending on the nature of the material to be stabilized, on the end use and on the presence of other additives. In general, it is appropriate to use for example 0.01 to 10% or 0.01 to 5% of the compound of the formula (IA), relative to the weight of the material to be stabilized (or the rubber content), preferably 0.05 to 2% or 0.05 to 1% or 0.1 to 5% or 0.2 to 3%.

The compounds of this invention can be added, for example, to the polymeric materials before, during or after the polymerization or crosslinking of the said materials. Furthermore, they can be incorporated in the polymeric materials in the pure form or encapsulated in waxes, oils or polymers.

In general, the compounds of this invention can be incorporated in the polymeric materials by various processes, such as dry mixing in the form of powder, or wet mixing in the form of solutions or suspensions or also in the form of a masterbatch which contains the compounds of this invention in a concentration of 2.5 to 25% by weight; in such operations, the polymer can be used in the form of powder, granules, solutions, suspensions or in the form of latices.

The materials stabilized with the compounds of this invention can be used for the production of mouldings, films, tapes, monofilaments, fibres, surface coatings and the like; or colored tires, weathering strips, gaskets, sealings, roofing membranes, various technical rubber articles (hose, tubes) or boots.

If desired, other conventional additives for synthetic polymers, such as antioxidants, UV absorbers, nickel stabilizers, pigments, fillers, plasticizers, corrosion inhibitors and metal deactivators, can be added to the organic materials containing the compounds of this invention.

Particular examples of said conventional additives are:

1. Antioxidants

1.1. Alkylated monophenols, for example 2,6-di-tert-butyl-4-methylphenol, 2-tert-butyl-4,6-dimethylphenol, 2,6-di-tert-butyl-4-ethylphenol, 2,6-di-tert-butyl-4-n-butylphenol, 2,6-di-tert-butyl-4-isobutylphenol, 2,6-dicyclopentyl-4-methylphenol, 2-(α-methylcyclohexyl)-4,6-dimethylphenol, 2,6-dioctadecyl-4-methylphenol, 2,4,6-tricyclohexylphenol, 2,6-di-tert-butyl-4-methoxymethylphenol, nonylphenols which are linear or branched in the side chains, for example, 2,6-di-nonyl-4-methylphenol, 2,4-dimethyl-6-(1′-methylundec-1′-yl)phenol, 2,4-dimethyl-6-(1′-methylheptadec-1′-yl)phenol, 2,4-dimethyl-6-(1′-methyltridec-1′-yl)phenol and mixtures thereof.

1.2. Alkylthiomethylphenols, for example 2,4-dioctylthiomethyl-6-tert-butylphenol, 2,4-dioctylthiomethyl-6-methylphenol, 2,4-dioctylthiomethyl-6-ethylphenol, 2,6-di-dodecylthiomethyl-4-nonylphenol.

1.3. Hydroquinones and alkylated hydroquinones, for example 2,6-di-tert-butyl-4-methoxyphenol, 2,5-di-tert-butylhydroquinone, 2,5-di-tert-amylhydroquinone, 2,6-diphenyl-4-octadecyloxyphenol, 2,6-di-tert-butylhydroquinone, 2,5-di-tert-butyl-4-hydroxyanisole, 3,5-di-tert-butyl-4-hydroxyanisole, 3,5-di-tert-butyl-4-hydroxyphenyl stearate, bis-(3,5-di-tert-butyl-4-hydroxyphenyl) adipate.

1.4. Tocopherols, for example α-tocopherol, β-tocopherol, γ-tocopherol, 67 -tocopherol and mixtures thereof (Vitamin E).

1.5. Hydroxalated thiodiphenyl ethers, for example 2,2′-thiobis(6-tert-butyl-4-methylphenol), 2,2′-thiobis(4-octylphenol), 4,4′-thiobis(6-tert-butyl-3-methylphenol), 4,4′-thiobis(6-tert-butyl-2-methylphenol), 4,4′-thiobis-(3,6-di-sec-amylphenol), 4,4′-bis(2,6-dimethyl-4-hydroxyphenyl)disulfide.

1.6. Alkylidenebisphenols, for example 2,2′-methylenebis(6-tert-butyl-4-methylphenol), 2,2′-methylenebis(6-tert-butyl-4-ethylphenol), 2,2′-methylenebis[4-methyl-6-(α-methylcyclohexyl)-phenol], 2,2′-methylenebis(4-methyl-6-cyclohexylphenol), 2,2′-methylenebis(6-nonyl-4-methylphenol), 2,2′-methylenebis(4,6-di-tert-butylphenol), 2,2′-ethylidenebis(4,6-di-tert-butylphenol), 2,2′-ethylidenebis(6-tert-butyl-4-isobutylphenol), 2,2′-methylenebis[6-(α-methylbenzyl)-4-nonylphenol], 2,2′-methylenebis[6-(α,α-dimethylbenzyl)-4-nonylphenol], 4,4′-methylenebis-(2,6-di-tert-butylphenol), 4,4′-methylenebis(6-tert-butyl-2-methylphenol), 1,1-bis(5-tert-butyl-4-hydroxy-2-methylphenyl)butane, 2,6-bis(3-tert-butyl-5-methyl-2-hydroxybenzyl)-4-methylphenol, 1,1,3-tris(5-tert-butyl-4-hydroxy-2-methylphenyl)butane, 1,1-bis(5-tert-butyl-4-hydroxy-2-methyl-phenyl)-3-n-dodecylmercaptobutane, ethylene glycol bis[3,3-bis(3′-tert-butyl-4′-hydroxyphenyl)butyrate], bis(3-tert-butyl-4-hydroxy-5-methyl-phenyl)dicyclopentadiene, bis[2-(3′-tert-butyl-2′-hydroxy-5′-methylbenzyl)-6-tert-butyl-4-methylphenyl]terephthalate, 1,1-bis-(3,5-dimethyl-2-hydroxyphenyl)butane, 2,2-bis-(3,5-di-tert-butyl-4-hydroxyphenyl)propane, 2,2-bis-(5-tert-butyl-4-hydroxy2-methylphenyl)-4-n-dodecylmercaptobutane, 1,1,5,5-tetra-(5-tert-butyl-4-hydroxy-2-methylphenyl)pentane.

1.7. O-, N- and S-benzyl compounds, for example 3,5,3′,5′-tetra-tert-butyl-4,4′-dihydroxydibenzyl ether, octadecyl-4-hydroxy-3,5-dimethylbenzylmercaptoacetate, tridecyl-4-hydroxy-3,5-di-tert-butylbenzylmercaptoacetate, tris(3,5-di-tert-butyl-4-hydroxybenzyl)amine, bis(4-tert-butyl-3-hydroxy-2,6-dimethylbenzyl)dithioterephthalate, bis(3,5-di-tert-butyl-4-hydroxybenzyl)sulfide, isooctyl-3,5-di-tert-butyl-4-hydroxybenzylmercaptoacetate.

1.8. Hydroxybenzylated malonates, for example dioctadecyl-2,2-bis-(3,5-di-tert-butyl-2-hydroxybenzyl)-malonate, di-octadecyl-2-(3-tert-butyl-4-hydroxy-5-methylbenzyl)-malonate, di-dodecylmercaptoethyl-2,2-bis-(3,5-di-tert-butyl-4-hydroxybenzyl)malonate, bis[4-(1,1,3,3-tetramethylbutyl)phenyl]-2,2-bis(3,5-di-tert-butyl-4-hydroxybenzyl)malonate.

1.9. Aromatic hydroxybenzyl compounds, for example 1,3,5-tris-(3,5-di-tert-butyl-4-hydroxybenzyl)-2,4,6-trimethylbenzene, 1,4-bis(3,5-di-tert-butyl-4-hydroxybenzyl)-2,3,5,6-tetramethylbenzene, 2,4,6-tris(3,5-di-tert-butyl-4-hydroxybenzyl)phenol.

1.10. Triazine Compounds, for example 2,4-bis(octylmercapto)-6-(3,5-di-tert-butyl-4-hydroxyanilino)-1,3,5-triazine, 2-octylmercapto-4,6-bis(3,5-di-tert-butyl-4-hydroxyanilino)-1,3,5-triazine, 2-octylmercapto-4,6-bis(3,5-di-tert-butyl-4-hydroxyphenoxy)-1,3,5-triazine, 2,4,6-tris(3,5-di-tert-butyl-4-hydroxyphenoxy)-1,2,3-triazine, 1,3,5-tris-(3,5-di-tert-butyl-4-hydroxybenzyl)isocyanurate, 1,3,5-tris(4-tert-butyl-3-hydroxy-2,6-dimethylbenzyl)isocyanurate, 2,4,6-tris-(3,5-di-tert-butyl-4-hydroxyphenylethyl)-1,3,5-triazine, 1,3,5-tris(3,5-di-tert-butyl-4-hydroxyphenylpropionyl)-hexahydro-1,3,5-triazine, 1,3,5-tris(3,5-dicyclohexyl-4-hydroxybenzyl)isocyanurate.

1.11. Benzylphosphonates, for example dimethyl-2,5-di-tert-butyl-4-hydroxybenzylphosphonate, diethyl-3,5-di-tert-butyl-4-hydroxybenzylphosphonate, dioctadecyl3,5-di-tert-butyl-4-hydroxybenzylphosphonate, dioctadecyl-5-tert-butyl-4-hydroxy-3-methylbenzylphosphonate, the calcium salt of the monoethyl ester of 3,5-di-tert-butyl-4-hydroxybenzylphosphonic acid.

1.12. Acylaminophenols, for example 4-hydroxylauranilide, 4-hydroxystearanilide, octyl N-(3,5-di-tert-butyl-4-hydroxyphenyl)carbamate.

1.13. Esters of β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionic acid with mono- or polyhydric alcohols, e.g. with methanol, ethanol, n-octanol, i-octanol, octadecanol, 1,6-hexanediol, 1,9-nonanediol, ethylene glycol, 1,2-propanediol, neopentyl glycol, thiodiethylene glycol, diethylene glycol, triethylene glycol, pentaerythritol, tris(hydroxyethyl) isocyanurate, N,N′-bis(hydroxyethyl)oxamide, 3-thiaundecanol, 3-thiapentadecanol, trimethylhexanediol, trimethylolpropane, 4-hydroxymethyl-1-phospha-2,6,7-trioxabicyclo[2.2.2]octane.

1.14. Esters of β-(5-tert-butyl-4-hydroxy-3-methylphenyl)propionic acid with mono- or polyhydric alcohols, e.g. with methanol, ethanol, n-octanol, i-octanol, octadecanol, 1,6-hexanediol, 1,9-nonanediol, ethylene glycol, 1,2-propanediol, neopentyl glycol, thiodiethylene glycol, diethylene glycol, triethylene glycol, pentaerythritol, tris(hydroxyethyl) isocyanurate, N,N′-bis-(hydroxyethyl)oxamide, 3-thiaundecanol, 3-thiapentadecanol, trimethylhexanediol, trimethylolpropane, 4-hydroxymethyl-1-phospha-2,6,7-trioxabicyclo[2.2.2]octane.

1.15. Esters of β-(3,5-dicyclohexyl-4-hydroxyphenyl)propionic acid with mono- or polyhydric alcohols, e.g. with methanol, ethanol, octanol, octadecanol, 1,6-hexanediol, 1,9-nonanediol, ethylene glycol, 1,2-propanediol, neopentyl glycol, thiodiethylene glycol, diethylene glycol, triethylene glycol, pentaerythritol, tris(hydroxyethyl)isocyanurate, N,N′-bis(hydroxyethyl)oxamide, 3-thiaundecanol, 3-thiapentadecanol, trimethylhexanediol, trimethylolpropane, 4-hydroxymethyl-1-phospha-2,6,7-trioxabicyclo[2.2.2]octane.

1.16. Esters of 3,5-di-tert-butyl-4-hydroxyphenyl acetic acid with mono- or polyhydric alcohols, e.g. with methanol, ethanol, octanol, octadecanol, 1,6-hexanediol, 1,9-nonanediol, ethylene glycol, 1,2-propanediol, neopentyl glycol, thiodiethylene glycol, diethylene glycol, triethylene glycol, pentaerythritol, tris(hydroxyethyl)isocyanurate, N,N′-bis(hydroxyethyl)oxamide, 3-thiaundecanol, 3-thiapentadecanol, trimethylhexanediol, trimethylolpropane, 4-hydroxymethyl-1-phospha-2,6,7-trioxabicyclo[2.2.2]octane.

1.17. Amides of β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionic acid e.g. N,N′-bis(3,5-di-tert-butyl-4-hydroxyphenylpropionyl)hexamethylenediamide, N,N′-bis(3,5-di-tert-butyl-4-hydroxyphenylpropionyl)trimethylenediamide, N,N′-bis(3,5-di-tert-butyl-4-hydroxyphenylpropionyl)-hydrazide, N,N′-bis[2-(3-[3,5-di-tert-butyl-4-hydroxyphenyl]propionyloxy)ethyl]oxamide (Naugard®XL-1 supplied by Uniroyal).

1.18. Ascorbic Acid (Vitamin C)

1.19. Aminic antioxidants, for example N,N′-di-isopropyl-p-phenylenediamine, N,N′-di-sec-butyl-p-phenylenediamine, N,N′-bis(1,4-dimethylpentyl)-p-phenylenediamine, N,N′-bis(1-ethyl-3-methylpentyl)-p-phenylenediamine, N,N′-bis(1-methylheptyl)-p-phenylenediamine, N,N′-dicyclohexyl-p-phenylenediamine, N,N′-diphenyl-p-phenylenediamine, N,N′-bis(2-naphthyl)-p-phenylenediamine, N-isopropyl-N′-phenyl-p-phenylenediamine, N-(1,3-dimethylbutyl)-N′-phenyl-p-phenylenediamine, N-(1-methylheptyl)-N′-phenyl-p-phenylenediamine, N-cyclohexyl-N′-phenyl-p-phenlenediamine, 4-(p-toluenesulfamoyl)diphenylamine, N,N′-dimethyl-N,N′-di-sec-butyl-p-phenylenediamine, diphenylamine, N-allyldiphenylamine, 4-isopropoxydiphenylamine, N-phenyl-1-naphthylamine, N-(4-tert-octylphenyl)-1-naphthylamine, N-phenyl-2-naphthylamine, octylated diphenylamine, for example p,p′-di-tert-octyldiphenylamine, 4-n-butylaminophenol, 4-butyrylaminophenol, 4-nonanoylaminophenol, 4-dodecanoylaminophenol, 4-octadecanoylaminophenol, bis(4-methoxyphenyl)amine, 2,6-di-tert-butyl-4-dimethylaminomethylphenol, 2,4′-diaminodiphenylmethane, 4,4′-diaminodiphenylmethane, N,N,N′, N′-tetramethyl-4,4′-diaminodiphenylmethane, 1,2-bis[(2-methylphenyl)amino]ethane, 1,2-bis(phenylamino)-propane, (o-tolyl)biguanide, bis[4-(1′,3′-dimethylbutyl)phenyl]amine, tert-octytated N-phenyl-1-naphthylamine, a mixture of mono- and dialkylated tert-butyl/tert-octyldiphenylamines, a mixture of mono- and dialkylated nonyldiphenylamines, a mixture of mono- und dialkylated dodecyldiphenylamines, a mixture of mono- and dialkylated isopropyl/isohexyldiphenylamines, a mixture of mono- und dialkylated tert-butyldiphenylamines, 2,3-dihydro-3,3-dimethyl-4H-1,4-benzothiazine, phenothiazine, a mixture of mono- und dialkylated tert-butyl/tert-octylphenothiazines, a mixture of mono- und dialkylated tert-octyl-phenothiazines, N-allylphenothiazin, N,N,N′,N′-tetraphenyl-1,4-diaminobut-2-ene, N,N-bis(2,2,6,6-tetramethylpiperid-4-yl-hexamethylenediamine, bis(2,2,6,6-tetramethylpiperid-4-yl)sebacate, 2,2,6,6-tetramethylpiperidin-4-one, 2,2,6,6-tetramethylpiperidin-4-ol.

2. UV Absorbers and Light Stabilisers

2.1. 2-(2′-Hydroxyphenyl)benzotriazoles, for example 2-(2′-hydroxy-5′-methylphenyl)-benzotriazole, 2-(3′,5′-di-tert-butyl-2′-hydroxyphenyl)benzotriazole, 2-(5′-tert-butyl-2′-hydroxyphenyl)benzotriazole, 2-(2′-hydroxy-5′-(1,1,3,3-tetramethylbutyl)phenyl)benzotriazole, 2-(3′,5′-di-tert-butyl-2′-hydroxyphenyl)-5-chloro-benzotriazole, 2-(3′-tert-butyl-2′-hydroxy-5′-methylphenyl)-5-chloro-benzotriazole, 2-(3′-sec-butyl-5′-tert-butyl-2′-hydroxyphenyl)benzotriazole, 2-(2′-hydroxy-4′-octyloxyphenyl)benzotriazole, 2-(3′,5′-di-tert-amyl-2′-hydroxyphenyl)benzotriazole, 2-(3′,5′-bis-(α,α-dimethylbenzyl)-2′-hydroxyphenyl)benzotriazole, 2-(3′-tert-butyl-2′-hydroxy-5′-(2-octyloxycarbonylethyl)phenyl)-5-chloro-benzotriazole, 2-(3′-tert-butyl-5′-[2-(2-ethylhexyloxy)-carbonylethyl]-2′-hydroxyphenyl)-5-chloro-benzotriazole, 2-(3′-tert-butyl-2′-hydroxy-5′-(2-methoxycarbonylethyl)phenyl)-5-chloro-benzotriazole, 2-(3′-tert-butyl-2′-hydroxy-5′-(2-methoxycarbonylethyl)phenyl)benzotriazole, 2-(3′-tert-butyl-2′-hydroxy-5′-(2-octyloxycarbonylethyl)phenyl)benzotriazole, 2-(3′-tert-butyl-5′-[2-(2-ethylhexyloxy)carbonylethyl]-2′-hydroxyphenyl)benzotriazole, 2-(3′-dodecyl-2′-hydroxy-5′-methylphenyl)benzotriazole, 2-(3′-tert-butyl-2′-hydroxy-5′-(2-isooctyloxycarbonylethyl)phenylbenzotriazole, 2,2′-methylene-bis[4-(1,1,3,3-tetramethylbutyl)-6-benzotriazole-2-ylphenol]; the transesterification product of 2-[3′-tert-butyl-5′-(2-methoxycarbonylethyl)-2′-hydroxyphenyl]-2H-benzotriazole with polyethylene glycol 300; [R—CH₂CH₂—COO—CH₂CH₂

₂ where R=3′-tert-butyl-4′-hydroxy-5′-2H-benzotriazol-2-ylphenyl, 2-[2′-hydroxy-3′-(α,α-dimethylbenzyl)-5′-(1,1,3,3-tetramethylbutyl)-phenyl]benzotriazole; 2-[2′-hydroxy-3′-(1,1,3,3-tetramethylbutyl)-5′-(α,α-dimethylbenzyl)-phenyl]benzotriazole.

2.2. 2-Hydroxybenzophenones, for example the 4-hydroxy, 4-methoxy, 4-octyloxy, 4-decyloxy, 4-dodecyloxy, 4-benzyloxy, 4,2′,4′-trihydroxy and 2′-hydroxy-4,4′-dimethoxy derivatives.

2.3. Esters of substituted and unsubstituted benzoic acids, as for example 4-tertbutyl-phenyl salicylate, phenyl salicylate, octylphenyl salicylate, dibenzoyl resorcinol, bis(4-tert-butylbenzoyl) resorcinol, benzoyl resorcinol, 2,4-di-tert-butylphenyl 3,5-di-tert-butyl-4-hydroxybenzoate, hexadecyl 3,5-di-tert-butyl-4-hydroxybenzoate, octadecyl 3,5-di-tert-butyl-4-hydroxybenzoate, 2-methyl-4,6-di-tert-butylphenyl 3,5-di-tert-butyl-4-hydroxybenzoate.

2.4. Acrylates, for example ethyl α-cyano-β,β-diphenylacrylate, isooctyl α-cyano-β,β-diphenylacrylate, methyl α-carbomethoxycinnamate, methyl α-cyano-β methyl-p-methoxy-cinnamate, butyl α-cyano-β-methyl-p-methoxy-cinnamate, methyl α-carbomethoxy-p-methoxycinnamate and N-(β-carbomethoxy-β-cyanovinyl)-2-methylindoline.

2.5. Nickel compounds, for example nickel complexes of 2,2′-thio-bis-[4-(1,1,3,3-tetramethylbutyl)phenol], such as the 1:1 or 1:2 complex, with or without additional ligands such as n-butylamine, triethanolamine or N-cyclohexyldiethanolamine, nickel dibutyldithiocarbamate, nickel salts of the monoalkyl esters, e.g. the methyl or ethyl ester, of 4-hydroxy-3,5-di-tert-butylbenzylphosphonic acid, nickel complexes of ketoximes, e.g. of 2-hydroxy-4-methylphenyl undecylketoxime, nickel complexes of 1-phenyl-4-lauroyl-5-hydroxypyrazole, with or without additional ligands.

2.6. Sterically hindered amines, for example bis(2,2,6,6-tetramethyl-4-piperidyl)sebacate, bis(2,2,6,6-tetramethyl-4-piperidyl)succinate, bis(1,2,2,6,6-pentamethyl-4-piperidyl)sebacate, bis(1-octyloxy-2,2,6,6-tetramethyl-4-piperidyl)sebacate, bis(1,2,2,6,6-pentamethyl-4-piperidyl) n-butyl-3,5-di-tert-butyl-4-hydroxybenzylmalonate, the condensate of 1-(2-hydroxyethyl)-2,2,6,6-tetramethyl-4-hydroxypiperidine and succinic acid, linear or cyclic condensates of N,N′-bis(2,2,6,6-tetramethyl-4-piperidyl)hexamethylenediamine and 4-tert-octylamino-2,6-dichloro-1,3,5-triazine, tris(2,2,6,6-tetramethyl-4-piperidyl)nitrilotriacetate, tetrakis(2,2,6,6-tetramethyl-4-piperidyl)-1,2,3,4-butane-tetracarboxylate, 1,1′-(1,2-ethanediyl)-bis(3,3,5,5-tetramethylpiperazinone), 4-benzoyl-2,2,6,6-tetramethylpiperidine, 4-stearyloxy-2,2,6,6-tetramethylpiperidine, bis(1,2,2,6,6-pentamethylpiperidyl)-2-n-butyl-2-(2-hydroxy-3,5-di-tert-butylbenzyl)malonate, 3-n-octyl-7,7,9,9-tetramethyl-1,3,8-triazaspiro[4.5]decan-2,4-dione, bis(1-octyloxy-2,2,6,6-tetramethylpiperidyl)sebacate, bis(1-octyloxy-2,2,6,6-tetramethylpiperidyl)succinate, linear or cyclic condensates of N,N′-bis-(2,2,6,6-tetramethyl-4-piperidyl)hexamethylenediamine and 4-morpholino-2,6-dichloro-1,3,5-triazine, the condensate of 2-chloro-4,6-bis(4-n-butylamino-2,2,6,6-tetramethylpiperidyl)-1,3,5-triazine and 1,2-bis(3-aminopropylamino)ethane, the condensate of 2-chloro-4,6-di-(4-n-butylamino-1,2,2,6,6-pentamethylpiperidyl)-1,3,5-triazine and 1,2-bis-(3-aminopropylamino)ethane, 8-acetyl-3-dodecyl-7,7,9,9-tetramethyl-1,3,8-triazaspiro[4.5]decane-2,4-dione, 3-dodecyl-1-(2,2,6,6-tetramethyl-4-piperidyl)pyrrolidin-2,5-dione, 3-dodecyl-1-(1,2,2,6,6-pentamethyl-4-piperidyl)pyrrolidine-2,5-dione, a mixture of 4-hexadecyloxy- and 4-stearyloxy-2,2,6,6-tetramethylpiperidine, a condensation product of N,N′-bis(2,2,6,6-tetramethyl-4-piperidyl)hexamethylenediamine and 4-cyclohexylamino-2,6-dichloro-1,3,5-triazine, a condensation product of 1,2-bis(3-aminopropylamino)ethane and 2,4,6-trichloro-1,3,5-triazine as well as 4-butylamino-2,2,6,6-tetramethylpiperidine (CAS Reg. No. [136504-96-6]); N-(2,2,6,6-tetramethyl-4-piperidyl)-n-dodecylsuccinimid, N-(1,2,2,6,6-pentamethyl-4-piperidyl)-n-dodecylsuccinimid, 2-undecyl-7,7,9,9-tetramethyl-1-oxa-3,8-diaza-4-oxo-spiro[4,5]decane, a reaction product of 7,7,9,9-tetramethyl-2-cycloundecyl-1-oxa-3,8-diaza-4-oxospiro [4,5]decane und epichlorohydrin, 1,1-bis(1,2,2,6,6-pentamethyl-4-piperidyloxycarbonyl)-2-(4-methoxyphenyl)ethene, N,N′-bis-formyl-N,N′-bis(2,2,6,6-tetramethyl-4-piperidyl)hexamethylenediamine, diester of 4-methoxy-methylene-malonic acid with 1,2,2,6,6-pentamethyl-4-hydroxypiperidine, poly[nethylpropyl-3-oxy-4-(2,2,6,6-tetramethyl-4-piperidyl)]siloxane, reaction product of maleic acid anhydride-α-olefin-copolymer with 2,2,6,6-tetramethyl-4-aminopiperidine or 1,2,2,6,6-pentamethyl-4-aminopiperidine.

2.7. Oxamides, for example 4,4′-dioctyloxyoxanilide, 2,2′-diethoxyoxanilide, 2,2′-dioctyloxy-5,5′-di-tert-butoxanilide, 2,2′-didodecyloxy-5,5′-di-tert-butoxanilide, 2-ethoxy-2′-ethyloxanilide, N,N′-bis(3-dimethylaminopropyl)oxamide, 2-ethoxy-5-tert-butyl-2′-ethoxanilide and its mixture with 2-ethoxy-2′-ethyl-5,4′-di-tert-butoxanilide, mixtures of o- and p-methoxy-disubstituted oxanilides and mixtures of o- and p-ethoxy-disubstituted oxanilides.

2.8. 2-(2-Hydroxyphenyl)-1,3,5-triazines, for example 2,4,6-tris(2-hydroxy-4-octyloxyphenyl)-1,3,5-triazine, 2-(2-hydroxy-4-octyloxyphenyl)-4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine, 2-(2,4-dihydroxyphenyl)-4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine, 2,4-bis(2-hydroxy-4-propyloxyphenyl)-6-(2,4-dimethylphenyl)-1,3,5-triazine, 2-(2-hydroxy-4-octyloxyphenyl)-4,6-bis(4-methylphenyl)-1,3,5-triazine, 2-(2-hydroxy-4-dodecyloxyphenyl)-4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine, 2-(2-hydroxy-4-tridecyloxyphenyl)-4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine, 2-[2-hydroxy-4-(2-hydroxy-3-butyloxy-propoxy)phenyl]-4,6-bis(2,4-dimethyl)-1,3,5-triazine, 2-[2-hydroxy-4-(2-hydroxy-3-octyloxy-propyloxy)phenyl]-4,6-bis(2,4-dimethyl)-1,3,5-triazine, 2-[4-(dodecyloxy/tridecyloxy-2-hydroxypropoxy)-2-hydroxy-phenyl]-4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine, 2-[2-hydroxy-4-(2-hydroxy-3-dodecyloxy-propoxy)phenyl]-4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine, 2-(2-hydroxy-4-hexyloxy)phenyl-4,6-diphenyl-1,3,5-triazine, 2-(2-hydroxy-4-methoxyphenyl)-4,6-diphenyl-1,3,5-triazine, 2,4,6-tris[2-hydroxy-4-(3-butoxy-2-hydroxy-propoxy)phenyl]-1,3,5-triazine, 2-(2-hydroxyphenyl)-4-(4-methoxyphenyl)-6-phenyl-1,3,5-triazine, 2-{2-hydroxy-4-[3-(2-ethylhexyl-1-oxy)-2-hydroxypropyloxy]phenyl}-4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine.

3. Metal deactivators, for example N,N′-diphenyloxamide, N-salicylal-N′-salicyloyl hydrazine, N,N′-bis(salicyloyl) hydrazine, N,N′-bis(3,5-di-tert-butyl-4-hydroxyphenylpropionyl) hydrazine, 3-salicyloylamino-1,2,4-triazole, bis(benzylidene)oxalyl dihydrazide, oxanilide, isophthaloyl dihydrazide, sebacoyl bisphenylhydrazide, N,N′-diacetyladipoyl dihydrazide, N,N′-bis(salicyloyl)oxalyl dihydrazide, N,N′-bis(salicyloyl)thiopropionyl dihydrazide.

4. Phosphites and phosphonites, for example triphenyl phosphite, diphenyl alkyl phosphites, phenyl dialkyl phosphites, tris(nonylphenyl) phosphite, trilauryl phosphite, trioctadecyl phosphite, distearyl pentaerythritol diphosphite, tris(2,4-di-tert-butylphenyl) phosphite, diisodecyl pentaerythritol diphosphite, bis(2,4-di-tert-butylphenyl) pentaerythritol diphosphite, bis(2,6-di-tert-butyl-4-methylphenyl)-pentaerythritol diphosphite, diisodecyloxypentaerythritol diphosphite, bis(2,4-di-tert-butyl-6-methylphenyl)pentaerythritol diphosphite, bis(2,4,6-tris(tert-butylphenyl)pentaerythritol diphosphite, tristearyl sorbitol triphosphite, tetrakis(2,4-di-tert-butylphenyl) 4,4′-biphenylene diphosphonite, 6-isooctyloxy-2,4,8,10-tetra-tert-butyl-12H-dibenz-[d,g]-1,3,2-dioxaphosphocin, bis(2,4-di-tert-butyl-6-methylphenyl) methyl phosphite, bis(2,4-di-tert-butyl-6-methylphenyl) ethyl phosphite, 6-fluoro-2,4,8,10-tetra-tert-butyl-12-methyl-di-benz[d,g]-1,3,2-dioxaphosphocin, 2,2′,2″-nitrilo[triethyltris(3,3′,5,5′-tetra-tert-butyl-1,1′-biphenyl-2,2′-diyl)phosphite], 2-ethylhexyl(3,3′,5,5′-tetra-tert-butyl-1,1′-biphenyl-2,2′-diyl)phosphite, 5-butyl-5-ethyl-2-(2,4,6-tri-tert-butylphenoxy)-1,3,2-dioxaphosphirane.

Especially preferred are the following phosphites:

Tris(2,4-di-tert-butylphenyl) phosphite (Irgafos®168, Ciba-Geigy), tris(nonylphenyl) phosphite,

5. Hydroxylamines, for example, N,N-di-benzylhydroxylamine, N,N-diethylhydroxylamine, N,N-dioctylhydroxylamine, N,N-dilaurylhydroxylamine, N,N-ditetradecylhydroxylamine, N,N-dihexadecylhydroxylamine, N,N-dioctadecylhydroxylamine, N-hexadecyl-N-octadecylhydroxylamine, N-heptadecyl-N-octadecylhydroxylamine, N,N-dialkylhydroxylamine derived from hydrogenated tallow amine.

6. Nitrones, for example, N-benzyl-alpha-phenyl-nitrone, N-ethyl-alpha-methyl-nitrone, N-octyl-alpha-heptyl-nitrone, N-lauryl-alpha-undecyl-nitrone, N-tetradecyl-alpha-tridcyl-nitrone, N-hexadecyl-alpha-pentadecyl-nitrone, N-octadecyl-alpha-heptadecyl-nitrone, N-hexadecyl-alpha-heptadecyl-nitrone, N-ocatadecyl-alpha-pentadecyl-nitrone, N-heptadecyl-alpha-heptadecyl-nitrone, N-octadecyl-alpha-hexadecyl-nitrone, nitrone derived from N,N-dialkylhydroxylamine derived from hydrogenated tallow amine.

7. Thiosynergists, for example, dilauryl thiodipropionate or distearyl thiodipropionate.

8. Peroxide scavengers, for example esters of thiodipropionic acid, for example the lauryl, stearyl, myristyl or tridecyl esters, mercaptobenzimidazole or the zinc salt of 2-mercaptobenzimidazole, zinc dibutyldithiocarbamate, dioctadecyl disulfide, pentaerythritol tetrakis(β-dodecylmercapto)propionate.

9. Polyamide stabilisers, for example, copper salts in combination with iodides and/or phosphorus compounds and salts of divalent manganese.

10. Basic co-stabilisers, for example, melamine, polyvinylpyrrolidone, dicyandiamide, triallyl cyanurate, urea derivatives, hydrazine derivatives, amines, polyamides, polyurethanes, alkali metal salts and alkaline earth metal salts of higher fatty acids for example calcium stearate, zinc stearate, magnesium behenate, magnesium stearate, sodium ricinoleate and potassium palmitate, antimony pyrocatecholate or zink pyrocatecholate.

11. Nucleating agents, for example, inorganic substances such as talcum, metal oxides such as titanium dioxide or magnesium oxide, phosphates, carbonates or sulfates of, preferably, alkaline earth metals; organic compounds such as mono- or polycarboxylic acids and the salts thereof, e.g. 4-tert-butylbenzoic acid, adipic acid, diphenylacetic acid, sodium succinate or sodium benzoate; polymeric compounds such as ionic copolymers (ionomers). Especially preferred are 1,3:2,4-bis(3′,4′-dimethylbenzylidene)sorbitol, 1,3:2,4-di(paramethyldibenzylidene)sorbitol, und 1,3:2,4-di(benzylidene)sorbitol.

12. Fillers and reinforcing agents, for example, calcium carbonate, silicates, glass fibres, glass bulbs, asbestos, talc, kaolin, mica, barium sulfate, metal oxides and hydroxides, carbon black, graphite, wood flour and flours or fibers of other natural products, synthetic fibers.

13. Other additives, for example, plasticisers, lubricants, emulsifiers, pigments, rheology additives, catalysts, flow-control agents, optical brighteners, flameproofing agents, antistatic agents and blowing agents.

14. Benzofuranones and indolinones, for example those disclosed in U.S. Pat. Nos. 4,325,863; 4,338,244; 5,175,312; 5,216,052; 5,252,643; DE-A-4316611; DE-A-4316622; DE-A-4316876; EP-A-0589839 or EP-A-0591102 or 3-[4-(2-acetoxyethoxy)-phenyl]-5,7-di-tert-butyl-benzofuran-2-one, 5,7-di-tert-butyl-3-[4-(2-stearoyloxyethoxy)phenyl]benzofuran-2-one, 3,3′-bis[5,7-di-tert-butyl-3-(4-[2-hydroxyethoxy]phenyl)benzofuran-2-one], 5,7-di-tert-butyl-3-(4-ethoxyphenyl)benzofuran-2-one, 3-(4-acetoxy-3,5-dimethylphenyl)-5,7-di-tert-butyl-benzofuran-2-one, 3-(3,5-dimethyl-4-pivaloyloxyphenyl)-5,7-di-tert-butylbenzofuran-2-one, 3-(3,4-dimethylphenyl)-5,7-di-tert-butyl-benzofuran-2-one, 3-(2,3-dimethylphenyl)-5,7-di-tert-butyl-benzofuran-2-one.

The weight ratio of the compounds of this invention to the conventional additives may be for example 1:0.5 to 1:5.

Other materials which may be stabilized with the compounds of the formula (IA) are recording materials for photographic reproduction and other reprographic techniques as described for example in Research Disclosure 1990, 31429 (pages 474-480), GB-A-2,319,523 or DE-A-19,750,906, page 22, line 15 to page 105, line 32.

Thus, another embodiment of this invention is a recording material, in particular a photographic material, containing at least one compound of the formula (IA); with the proviso that the compound of the formula

is disclaimed.

Of special importance is also the stabilization of non-silver reprographic materials, for example, those used for pressure-sensitive copying systems, microcapsule photocopier systems, heat-sensitive copier systems and ink-jet printing.

The recording materials stabilized with the compounds of the formula (IA) have an unexpectedly high quality, especially in terms of their light stability.

The recording materials have a structure which is known per se and which corresponds to their utility. They consist of a base, for example a paper or plastic film, on which one or more coatings are applied. Depending on the type of the material, these coats contain the suitable components required. In the case of photographic materials, the coats contain for example silver halide emulsions, colour couplers, dyes and the like. The material intended for ink-jet printing has e.g. a customary base on which an absorption layer suitable for ink is located. Uncoated paper can likewise be employed for ink-jet printing. In the latter case, the paper simultaneously functions as a base and has the absorbent for the ink. Suitable materials for ink-jet printing are described, inter alia, in U.S. Pat. No. 5,073,448, the disclosure content of which is regarded as part of the present description.

The recording material can also be transparent, for example in the case of projection films.

The compound of the formula (IA) can be incorporated into the material even in the course of manufacture; in papermaking, for example, by addition to the pulp. Another method of use is the spraying of the material with an aqueous solution of the compound of the formula (IA), or the addition thereof to the coating.

Coatings for transparent recording materials for projection must not contain any light-scattering particles such as pigments or fillers.

The colour-binding coatings can contain further additives, for example antioxidants, light stabilizers (including UV absorbers and/or conventional hindered amine light stabilizers), viscosity improvers, brighteners, biocides and/or antistats.

The coating is usually prepared as described in the following. The water-soluble components, for example the binder, are dissolved in water and mixed. The solid components, for example fillers and other additives as already described, are dispersed in this aqueous medium. Dispersion is advantageously brought about with the aid of equipment such as ultrasonic devices, turbine agitators, homogenizers, colloid mills, bead mills, sand mills, high-speed stirrers and the like. A particular advantage of the compounds of the formula (IA) is that they can easily be incorporated into the coating.

As mentioned above, the recording materials cover a broad field of use. Compounds of the formula (IA) can be employed, for example, in pressure-sensitive copier systems. They can be added to the paper to protect the micro-encapsulated dye precursors against light, or to the binder of the developer layer for protecting the dyes formed therein.

Photocopier systems with light-sensitive microcapsules which are developed by pressure are described, inter alia, in U.S. Pat. Nos. 4,416,966, 4,483,912, 4,352,200, 4,535,050, 4,536,463, 4,551,407, 4,562,137 and 4,608,330 and also in EP-A-139,479, EP-A-162,664, EP-A-164,931, EP-A-237,024, EP-A-237,025 and EP-A-260,129. In all these systems, the compounds of the formula (IA) can be added to the colour-accepting layer. Alternatively, the compounds of the formula (IA) can be added to the donor layer for protecting the colour formers against light.

The compounds of the formula (IA) can also be employed in recording materials which are based on the principle of photopolymerization, photosoftening or the rupture of microcapsules, or, when heat-sensitive or photosensitive diazonium salts, leuco dyes with oxidizing agent or colour lactones with Lewis acids are used.

Heat-sensitive recording material exploits the colour-imparting reaction between a colourless or weakly coloured base dye and an organic or inorganic colour developer; the recorded image being produced by heat-induced contact of the two materials. This type of heat-sensitive recording material is very widespread, not only as the recording medium for faxes, computers, etc., but also in many other fields, for example in label printing.

The heat-sensitive recording material according to the present invention is composed of a base, a heat-sensitive colour-forming recording layer on this base, and, optionally, a protective layer on the heat-sensitive, colour-forming recording layer. The heat-sensitive, colour-forming recording layer contains as its principal constituent a colour-imparting compound and a colour-developing compound, and also a compound of the formula (IA). If a protective layer is present, the compound of the formula (IA) can also be incorporated into the protective layer.

Heat-sensitive recording materials are described, for example, in JP-A-Hei 8-267 915.

Further fields of use are recording materials for dye diffusion transfer printing, thermal wax transfer printing and dot matrix printing, and for use with electrostatic, electrographic, electrophoretic, magnetographic and laser-electrophotographic printers, recorders or plotters. Of the materials mentioned, preference is given to recording materials for dye diffusion transfer printing as described for example in EP-A-507,734.

Compounds of the formula (IA) can also be employed in inks (preferably for ink-jet printing) for example as described in U.S. Pat. No. 5,098,477, the disclosure content of which is regarded as part of the present description. The invention therefore preferably also relates to an ink comprising at least one compound of the formula (IA) as stabilizer. The ink, especially for ink-jet printing, contains preferably water. Inks contain the stabilizer of the formula (IA) usually in a concentration of from 0.01 to 20% by weight, in particular from 0.5 to 10% by weight.

The photographic material according to this invention can be a black and white or can be a colour photographic material. A colour photographic material is preferred.

Examples of colour photographic materials are colour negative films, colour reversal films, colour positive films, colour photographic paper, colour reversal photographic paper, colour-sensitive materials for the dye diffusion transfer process or the silver dye bleach process.

Details of the photographic materials to be stabilized according to this invention and components which can be employed therein are given, inter alia, in GB-A-2,319,523, DE-A-19,750,906, page 23, line 20 to page 105, line 32, and U.S. Pat. No. 5,538,840, column 25, line 60 to column 106, line 31. These parts of U.S. Pat. No. 5,538,840 are incorporated herein by way of reference.

The compounds of this invention can be introduced in any layer of a silver halide photographic material, however, they are preferably incorporated in a chromogenic layer, in particular in a layer containing a yellow coupler. They are used, for example, in a 1% to 200% weight ratio with the coupler, preferably 1% to 100%. The compounds of the present invention can be used in combination with other conventional stabilizers that can be incorporated in the same layer or in a different layer. Examples of suitable conventional stabilizers are described in GB-A-2,319,523, DE-A-19,750,906 and U.S. Pat. No. 5,538,840 and include in particular phenolic stabilizers, conventional hindered amine stabilizers, UV absorbers, preferably those of the hydroxyphenyl benztriazole type or of the hydroxyphenyl triazine class, and the like.

Examples of yellow couplers are also disclosed in U.S. Pat. No. 5,538,840, column 33, line 3 to column 47, line 15.

Thus, further preferred embodiments of this invention are:

(1) A photographic material comprising on a substrate at least one layer containing a compound of the formula (IA); with the proviso that the compound of the formula

is disclaimed.

(2) A silver halide colour photographic material comprising a support having thereon at least one light-sensitive silver halide emulsion layer and optionally a non-light sensitive emulsion layer, characterized in that at least one light-sensitive layer contains a compound of the formula (IA); with the proviso that the compound of the formula

is disclaimed.

(3) A silver halide colour photographic material comprising a support having thereon

-   a) at least one cyan-forming unit composed of a red-sensitive silver     halide emulsion layer containing a cyan dye-forming coupler, -   b) at least one magenta-forming unit composed of a green-sensitive     silver halide emulsion layer containing a magenta dye-forming     coupler and -   c) at least one yellow-forming unit composed of a blue-sensitive     silver halide emulsion layer containing a yellow dye-forming     coupler,     characterized in that -   the blue-sensitive layer contains a compound of the formula (IA).

The invention is illustrated in more detail by the following Examples. All percentages are by weight, unless otherwise indicated.

EXAMPLE 1 Preparation of the Compound of the Formula

A) Synthesis of the intermediate 2,2,5,5-tetramethyl-imidazolidin-4-thione. 238.6 g (4.11 mol) of acetone are added to a solution of 199.9 g (2.35 mol) of acetocyanhydride in 250 ml of water. Subsequently, 200 g (3.12 mol) of an aqueous solution of (NH₄)₂S (20% W/W) are slowly added to the mixture. After the addition, the mixture is left to react for 2 hours at room temperature and then is heated to 60° C. for additional two hours. After cooling to 10° C., the mixture is filtered off and the filtrate is washed twice with water.

B) 147 g (0.6 mol) of 1,6-dibromohexane and 200 g (1.45 mol) of potassium carbonate are added to a solution of 200 g (1.26 mol) of 2,2,5,5-tetramethyl-imidazolidin-4-thione in 1 l of methanol. Then, the mixture is refluxed for 12 hours. Subsequently, the mixture is evaporated under vacuum and 500 ml of water and

500 ml of CH₂Cl₂ are added. The organic layer is separated off, dried over sodium sulphate and then evaporated under vacuum. The compound obtained has a melting point of 101° C.

EXAMPLE 1-l Preparation of the Compound of the Formula

A) Synthesis of the intermediate 2,2,5,5-tetramethylimidazolidin-4-thione.

In a 2 l four necked flask equipped with a mechanical stirrer, thermometer, condenser and gas inlet tube, 525 ml of water, 143 g of NH₄Cl and 106.7 g of Na₂S are placed. The solution is stirred for 30 minutes and 102 g of acetone are added. To the solution obtained after 2 hours at 20-25° C., 85 g of acetone cyanohydrin are added dropwise. The mixture is left to react under stirring for additional 2 hours. The suspension obtained is heated to 60° C. and is stirred for additional 2 hours. Then, the suspension is heated to 85° C. and the NH₃ of the reaction is removed. The reaction mixture is cooled to 20° C. and a white solid is recovered, washed with 200 ml of water and dried at 30° C. under vacuum.

B) In a 2 l four necked flask equipped with a mechanical stirrer, thermometer, condenser and a gas inlet tube, 173 g of 2,2,5,5-tetramethylimidazolidin-4-thione, 77 g of 1,6-dichlorohexane and 360 ml of xylene are placed. The solution is heated to 135° C. and after 90 minutes a suspension is obtained. The reaction mixture is stirred for additional 18 hours. Then, the reaction mixture is cooled to 60° C. and a solution of 41.7 g of NaOH in 180 ml of water is added drop by drop. The organic layer is separated and washed twice with 100 ml of water. After the addition of 150 ml of water, the organic solution is slowly cooled to 10° C. and stirred for 1 hour. The suspension obtained is filtered, washed with water and dried in an oven. A solid compound with a melting range of 99-106° C. is obtained.

EXAMPLE 2 Preparation of the Compound of the Formula

A solution of 8.4 g (0.27 mol) of p-formaldehyde and 12.4 g (0.27 mol) of formic acid in 15 ml of water are slowly—during 2 hours—added to a solution of 40 g (0.11 mol) of the compound of Example 1B in 200 ml of toluene heated to 90° C. After the addition, the solution is left to react for additional two hours and then, the water is azeotropically distilled off. After 4 hours, the solution is cooled to room temperature and a solution of 41 g (0.30 mol) of K₂CO₃ in 100 ml of water is added. After ½ hour, the organic layer is separated off, washed twice with water, dried over sodium sulphate and evaporated under vacuum. The compound is crystallised by CH₃CN. A white powder has been obtained with a melting point of 70.3° C.

EXAMPLE 3 Preparation of the Compound of the Formula

64 g (0.60 mol) of Na₂CO₃ and 31 g (0.26 mol) of allylbromide are added to a solution of 100 g (0.25 mol) of the compound of Example 1B in 200 ml of methanol. The solution is refluxed under stirring for 8 hours. Then, the mixture is cooled to room temperature and evaporated under vacuum. The residue is dissolved in methylene chloride and washed twice with water. The organic layer is separated off, dried on sodium sulphate, and evaporated under vacuum. The desired product is a white powder with a melting range of 72-77° C.

EXAMPLE 4 Preparation of the Compound of the Formula

35 g (0.09 mol) of the compound of Example 1B are suspended in 200 ml of xylene and heated to reflux. The mixture is anhydrified via azeotropic distillation and then, it is cooled to 60° C. 27 g (0.26 mol) of acetic anhydride are added and the solution is refluxed for 6 hours. Subsequently, the mixture is cooled to room temperature and a solution of 56 g of Na₂CO₃ in 150 ml of water is added. The mixture is left to react for additional 3 hours at about 60° C. and then, it is filtered off at this temperature. The organic layer is separated off, washed twice with water, anhydrified over sodium sulphate and evaporated under vacuum. The desired product is a white powder with a melting range of 151-157° C.

EXAMPLE 5 Preparation of the Compound of the Formula

A) Synthesis of the Intermediate of the Formula

A solution of 300 g (3.17 mol) of chloroacetic acid, 136 g (1.51 mol) of 1,4-butanediole and 1 ml of sulphuric acid in 750 ml of toluene are heated to reflux and left to react for 4 hours. The water formed during the reaction is azeotropically distilled off. Then, the mixture is cooled to 70° C. and a solution of 25 g of Na₂CO₃ in 100 ml of water is added. After 20 min and at 7020 C., the organic layer is separated off, washed twice with water, dried over sodium sulphate and evaporated under vacuum. The product obtained is a pale yellow solid.

B) 131 g (0.99 mol) of K₂CO₃ are added at room temperature to a solution of 150 g (0.87 mol) of the compound of Example 1A in 700 ml of acetone, and 100 g (0.41 mol) of the compound of Example 5A are added. The mixture is left to react at room temperature for 30 hours. Then, the mixture is heated to 50° C. and filtered off. The solution is evaporated under vacuum. The desired product is a white powder with a melting range of 110-115° C.

EXAMPLE 6 Preparation of the Compound of the Formula

Using the procedure described in Example 2 and using as starting material the compound of Example 5B, the desired product is obtained as a white powder with a melting range of 75-82° C.

EXAMPLE 7 Preparation of the Compound of the Formula

A) Synthesis of the Intermediate of the Formula

Following the procedure reported in the Example 1-l and using chlorobutane as alkylating agent for 2,2,5,5-tetramethylimidazolidin-4-thione, a clear oil is obtained.

B) 88 g (0.4112 mol) of the product described under A) are dissolved in 200 ml of methanol, and subsequently 85 g (0.62 mol) of potassium carbonate and 74.5 g (0.62 mol) of allylbromide are added. The mixture is refluxed for 2 days. Then, the solvent is removed and the concentrate is dissolved in 200 ml of methylene chloride. The organic solution is washed twice with 100 ml of water. The organic layer is separated, dried on anhydrous sodium sulphate and evaporated under vacuum. A clear oil is obtained.

¹H NMR (300 MHz, CDCl₃):

δ=6.00 (m, 1H); 5.35-5.14 (m, 2H); 3.47-3.44 (d, 2H); 3.18-3.00 (t, 2H); 1.79-1.74 (m, 2H); 1.60-1.52 (m, 2H); 1.40-1.31 (m, 12H); 1.07-1.01 (t, 3H).

EXAMPLE 8 Preparation of the Compound of the Formula

Following the procedure reported in the Example 1-l and using chloroethanol as alkylating agent for 2,2,5,5-tetramethylimidazolidin-4-thione, a white solid with a melting range of 98-101° C. is obtained.

EXAMPLE 9 Preparation of the Compound of the Formula

Following the procedure reported in the Example 1-l and using epichlorohydrin as alkylating agent for 2,2,5,5-tetramethylimidazolidin-4-thione, a white, waxy product with a melting range of 41-46° C. is obtained.

EXAMPLE 10 Preparation of the Compound of the Formula

Following the procedure reported in Example 2 and using as starting material the product of Example 8, a pale orange oil is obtained.

¹H NMR (300 MHz, CDCl₃):

δ=5.35 (s, 1H); 3.88 (t, 2H); 3.15-3.12 (t, 2H); 2.25-2.23 (s, 3H); 1.23 (s, 6H; 1.18 (s, H).

EXAMPLE 11 Preparation of the Compound of the Formula

A mixture of 40 g (0.2531 mol) of 2,2,5,5-tetramethylimidazolidin-4-thione, 36 g (0.27 mol) of potassium chloroacetate and 42 g of potassium carbonate in 150 ml of methanol is left to react at room temperature for 70 hours. Then, the mixture is evaporated, and the solid residue is dissolved in 150 ml of water and acidified with 50 ml of a HCl solution (37% w/w). After one hour, the mixture is filtered off and a white solid with a melting range of 209-214° C. is recovered.

EXAMPLE A Stabilization of a Yellow Pigmented and Sulfur Crosslinked Ethylene-propylene-diene-elastomer (EPDM)

Recipe in parts by weight: EPDM (Buna ® AP 451) 100.0 Silica (Ultrasil ® VN 3) 30.0 Paraffin oil (Naftolen ® ND) 20.0 Stearic acid 1.0 ZnO 3.0 Carbowax 2.0 TiO₂ 2.0 4,6-Bis{octylthiomethyl}-o-cresol 0.5 Sulfur 1.5 Vulkacit ® CZ/C 1.0 Vulkacit ® Thiuram MS 0.8 Pigment Microlen ® Yellow MOO 138 3G 0.5 Light Stabilizer (see TABLE 1) 1.0

The components of the recipe are mixed at 70° C. in an open roll mill. For incorporation of the pigment, the temperature is raised to 110° C. The cure time at 160° C. is determined in a MDR 2000 rheometer.

2 mm plates are cured at 160° C. until t₉₅ of the rheometer curve (minutes to 95% of the rheometer curve maximum).

The rubber samples are exposed to artificial light in an ATLAS® CI 1200 Weather-O-meter without water spray. The Yellowness-Index (ΔYI) is periodically determined according to ASTM D 1925-70. The results are indicated in Table 1.

TABLE 1 Light Stabilizer ΔYI after 750 hours *) Without 37 Compound of Example 6 28 Compound of Example 2 26 *) = YI after 750 hours minus YI at 0 hours exposure (Low values are desired.)

EXAMPLE B Stabilization of a Yellow Pigmented and Peroxide Crosslinked Ethylene-propylene-diene-elastomer (EPDM)

Recipe in carts by weight: EPDM ( ® Buna AP 451) 100.0  ® PoleStar 200 R (white filler) 150.0 Paraffin oil ( ® Naftolen ND) 30.0 Stearic acid 0.5 Polyethylene wax (carbowax) 5.0 Tri-allyl-cyane-urathe (TAC 40) 2.0  ® Luperox 231 (peroxide 40%) 7.0 TiO₂ 2.0 Pigment  ® Microlene Yellow MOO 138 3G 0.5 Light Stabilizer (see TABLE 2) 1.0

The components of the recipe and the stabilizer listed in Table 2 are mixed at 70° C. in an open roll mill. For incorporation of the pigment, the temperature is raised to 110° C. Finally, the peroxide is incorporated at 70° C.

The cure time at 160° C. is determined in a MDR 2000 rheometer.

2 mm plates are cured at 160° C. until T₉₅ of the rheometer curve (minutes to 95% of the rheometer curve maximum).

The rubber samples are exposed to artificial light in an ®Atlas CI 1200 Weather-O-meter without water spray. The Yellowness-Index (Δ YI) is determined periodically according to ASTM D 1925-70.

The results are indicated in Table 2.

TABLE 2 Light Stabilizer ΔYI after 2000 hours*) Without −22 Compound of Example 2 −7 *)In peroxide crosslinked EPDM, the YI decreases due to chaulking; less decrease means better performance.

EXAMPLE C Stabilization of a Yellow Pigmented and Sulphur Crosslinked Styrene-butadiene-copolymer (SBR)

Recipe in parts by weight:  ® ESBR 1709 ( ® Enichem) 100.0 ZnO 5.0 Stearic acid 1.0  ® Winnofil/ICI (white filler) 50.0 Pigment  ® Microlene Yellow MOO 138 3G 0.5 TIO₂ (Rutile) 3.0 Sulphur 2.0  ® Vulkacit DM ( ® Bayer) 1.5  ® Vulkacit D ( ® Bayer) 0.5 Light Stabilizer (see TABLE 3) 1.6

The components of the recipe and the stabilizer listed in Table 3 are mixed at 70° C. in an open roll mill. For incorporation of the pigment, the temperature is raised to 110° C. The cure time at 130° C. is determined in a MDR 2000 rheometer.

2 mm plates are cured at 130° C. until T₉₅ of the rheometer curve (minutes to 95% of the rheometer curve maximum).

The rubber samples are exposed to artificial light in an ®Atlas CI 1200 Weather-O-meter without water spray. The Yellowness-Index (Δ YI) is determined periodically according to ASTM D 1925-70. The results are indicated in Table 3.

TABLE 3 ΔYI after Light Stabilizer 1000 hours*) Without 18 Compound of Example 2 plus  ® TINUVIN 213 13 (1:1 ratio) Compound of Example 5 plus  ® TINUVIN 213 11 (1:1 ratio)  ® TINUVIN 213 is the transesterification product of 2-[3′-tert-butyl-5′-(2-methoxycarbonylethyl)-2′-hydroxyphenyl]-2H-benzotriazole with polyethylene glycol 300. *)Higher numbers indicate stronger discolouration that means less protection.

EXAMPLE D Heat Stabilization of TPE (Oil Extended SEBS/PP 2:1 Blend)

0.05% of pentaerythrityl-tetrakis{3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate}, 0.05% of tris{2,4-di-tert-butylphenyl} phosphite, 0.2% of 2-(2′-hydroxy-3′-tert-butyl-5′-methylphenyl)-5-chlorobenzotriazole and 0.3% of the stabilizer indicated in Table 4 are incorporated in the SEBS/PP blend at 170° C. in an open roll mill. Then, 2 mm plates are compression molded at 170° C.

The plates are aged in a recirculating air oven at 130° C., and the Yellowness-Index (YI) and Delta E of the plates is periodically determined according to ASTM D 1925-70.

TABLE 4 After 20 days at 130° C.*) Stabilizer YI Delta C Compound of Example 2 43 13 *)Lower numbers indicate better stability.

EXAMPLE E Stabilization of a Violet Pigmented TPE (Oil Extended SEBS/PP 2:1 Blend)

0.05% of pentaerythrityl-tetrakis{3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate}, 0.05% of tris{2,4-di-tert-butylphenyl} phosphite and 0.3% of the stabilizer indicated in Table 5 are incorporated in the SEBS/PP blend at 170° C. in an open roll mill. Then, 2 mm plates are compression molded at 170° C.

The rubber samples are exposed to artificial light in an ®Atlas CI 4000 Weather-O-meter. The gloss according to DIN 67 530 at an angle of 60° is measured before and after 768 hours exposure. The results are listed in Table 5.

TABLE 5 Gloss Stabilizer before exposure after 768 hours exposure*) Without 59 13 Compound of Example 2 67 56 *)Higher gloss number after exposure indicates better stability.

EXAMPLE F Stabilization of TPO (Thermoplastic Polyolefins)

Polypropylene-copolymer (®DAPLEN KSR 4525, ®Borealis GmbH), 0.1% of calcium stearate, 15.0% of talcum (®Luzenac 00S), 0.25% of carbon black (®Printex P), 0.075% of tris{2,4-di-tert-butylphenyl} phosphite and the additive system indicated in Table 6 are mixed together for 2 minutes on a ®Henschel Mixer. The resulting mixture is compounded on a ®BERSTORFF X extruder (twin screw) at a maximum temperature of 220° C. The mixture is dried at 60° C. for 2 hours and then injection molded into plaques of 67 mm×42 mm×2 mm on a ®ENGEL HL 60 (conditions: nitrogen; processing temperature: max. 240° C.; mold temperature: 70° C.).

The resulting TPO plaques are exposed to accelerated weathering in a Weather-O-Meter ®ATLAS Ci 4000 (conditions: irradiation: 0.55 W/m²@ 340 nm; borosilicate/borosilicate filters; black panel temperature (BPT): 70° C.; dry bulb: 50° C.; 50% relative humidity (r.h.); cycle: 102 minutes dry/18 minutes wet; no dark phase).

The results are indicated in Table 6.

TABLE 6 Results after 500 hours accelerated weathering in a Weather-O-Meter ® ATLAS Ci 4000: Grey scale Delta E* Gloss 60° Additive system 0 h 500 h 0 h 500 h 0 h 500 h 0.075% of ® IRGANOX 1010 5 5 0 0.1 45 31 0.500% of the compound of Example 2 0.075% of ® IRGANOX 1010 5 5 0 0.1 42 29 0.250% of the compound of Example 2 0.250% of ® CHIMASSORB 2020 0.075% of ® IRGANOX 1076 5 5 0 0.1 40 30 0.500% of the compound of Example 2 Grey scale is measured according to ISO 105A02; 5 best, 0 worst result. Delta E* is measured according to DIN 6174 (CIELAB). Gloss (60° angle) is measured according to DIN 67530. ® IRGANOX 1010 = pentaerythrityl tetrakis{3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate} ® IRGANOX 1076 = octadecyl-3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate ® CHIMASSORB 2020 = the product of the formula

EXAMPLE G Stabilization of ABS (Acrylonitrile-Butadiene-Styrene)

200 g of ABS (Mass ABS, ®Magnum 3504 from ®Dow Chemical Corp.; or Emulsion ABS, ®Novodur PMT from ®Bayer Corp.), 0.525 g (0.250%) of 2-(2′-hydroxy-5′-methylphenyl)benzotriazole and 0.525 g (0.250%) of the compound of Example 2 are mixed together on a “tumbling barrel mixer” (“Rollbock”) during 15 hours. Then, the mixture is compounded on a two roll mill (®Schwabenthan W) at 160/170° C. (first roll/second roll) and 14/16 rpm (first roll/second roll) for 4 minutes.

The resulting sheets of 1-2 mm thickness are used to make plaques (175 mm×175 mm×2 mm) by compression molding at 185° C. on a ®Pasadena Hydraulics Press under the following conditions: press 1 minute and 15 seconds without pressure; then raise pressure to 20,000 pounds within 30 seconds; then quickly to 40,000 pounds. The pressure is maintained at 40,000 pounds for 1 minute and 30 seconds (total press time 3 minutes and 15 seconds). Finally, the plaques are cooled on a non-heated press under a pressure of 40,000 pounds.

The resulting ABS plaques are exposed to accelerated weathering in a Weather-O-Meter ®ATLAS Ci 65 (conditions: irradiation: 0.35 W/m²@ 340 nm; borosilicate/borosilicate filter; black panel temperature: 63° C.; no dark phase; 60% relative humidity; dry cycle (no rain)).

After the exposure, the gloss (60° angle) is measured according to DIN 67530. The results are shown in Table 7.

TABLE 7 Gloss after ABS 0 hours 250 hours 500 hours Mass 79 79 79 Emulsion 79 78 78

EXAMPLE H Corrosion Inhibition in an Acrylic Dispersion

To prepare the coating composition based on an acrylic dispersion, components 2-10 (formulation without corrosion inhibitor) or components 1-10 (formulation comprising the corrosion inhibitor) are employed in the sequence shown below.

Ingredients % by weight 1. Corrosion inhibitor 0.47 2. Demineralized water 3.10 3. Ammonium hydroxide solution (25%) Adjust to pH 8-8.5 4.  ® Methylcarbitol ^(a)) 5.00 5.  ® Orotan 165 ^(b)) 0.82 6.  ® Triton CF 10 ^(c)) 0.29 7.  ® Drew Plus TS 4380 ^(d)) 0.28 8.  ® Acrysol RM 8 ^(e)) 0.60 9.  ® Kronos RN 56 ^(f)) 5.72 10.  ® Millicarb ^(g)) 17.40 11. Butyldiglykol 3.67 12.  ® Maincote HG 54 ^(h)) 58.70 13.  ® Texanol ^(i)) 1.50 14. Dibutylphthalate ^(j)) 1.50 15.  ® Drew T 4310 ^(k)) 0.32 16. Ammonium hydroxide solution (25%) 0.30 Total 100.0 Total solids: 47%; pH: 8-8.5 ^(a)) ® Methylcarbitol: diethylene glycol monomethylether ( ® Union Carbide) ^(b)) ® Orotan 165: dispersing agent ( ® Rohm & Haas) ^(c)) ® Triton CF 10: nonionic wetting agent ( ® Rohm & Haas) ^(d)) ® Drew Plus TS 4380: defoamer ( ® Drew Chem. Corp.) ^(e)) ® Acrysol RM 8: nonionic thickener ( ® Rohm & Haas) ^(f)) ® Kronos RN 56: titanium dioxide ( ® Kronos GmbH) ^(g)) ® Millicarb: calcium carbonate ( ® Omya) ^(h)) ® Maincote HG 54: acrylic dispersion, 41.5% in demineralized water ( ® Rohm & Haas) ^(i)) ® Texanol: coalescent ( ® Eastman Cem. Prod. Inc.) ^(j)) Dibutylphthalate: plasticizer ( ® Eastman Cem. Prod. Inc.) ^(k)) ® Drew T 4310: defoamer ( ® Drew Chain. Corp.)

Components 1 to 10 or 2 to 10 are dispersed to a grinding fineness or grinding particle size of <15 μm using a high speed stirrer at 3000 rpm. The dispresing result of the pigment paste thus obtained is evaluated by determination of the grindometer value (ISO 1524). The amount of corrosion inhibitor according to the invention employed is based on the total solids of the formulation without additive (total solids: 47%). Accordingly, for example, addition of 1% of corrosion inhibitor in 100 g of dispersion means an amount of 0.47 g. To finish the coating composition, components 11 to 16 are added in the sequence shown above at a reduced speed (1000 rpm). The pH of the formulation is then checked, and if necessary adjusted to a value of pH 8 to 8.5 using ammonium hydroxide solution (25%). The formulation is subsequently applied (e.g. by brushing, rolling, conventional spray or airless spray) to steel panels (19 cm×10.5 cm; cold rolled, degreased steel; producer: ®Chemetall GmbH, Frankfurt am Main, Germany) and allowed to cure under high humidity conditions: 30° C. (90% rel. humidity).

In the absence of the compound of Example 11 (=corrosion inhibitor), corrosion of the steel substrate occurs (flash rust) during the drying of the coating, whereas in its presence the steel substrate is fully protected.

EXAMPLE I

The compound of Example 6 is dissolved in 30 g of Solvesso®100^(e)) and tested in a clearcoat having the following composition.

Ingredients % by weight 1) Viacryl ® SC 303 ^(a)) 27.51 2) Viacryl ® SC 370 ^(b)) 23.34 3) Maprenal ® MF 650 ^(c)) 27.29 4) Butylacetate/Butanol (37/8) 4.33 5) Isobutanol 4.87 6) Solvesso ® 150 ^(d)) 2.72 7) Crystal Oil K-30 8.74 8) Levelling agent Baysilon ® MA ^(f)) 1.20 (1% in Solvesso 150) 100.00 g ^(a)) Acrylate resin,  ® Vianova Resins GmbH; 65% solution in xylene/butanol (26:9) ^(b)) Acrylate resin,  ® Vianova Resins GmbH; 75% solution in Solvesso ® 100 ^(d)) ^(c)) Melamine resin,  ® Vianova Resins GmbH; 55% solution in isobutanol ^(d, e)) aromatic hydrocarbon mixture, boiling range: 182-203° C. (Solvesso ® 150) or 161-178° C. (Solvesso ® 100); manufacturer:  ® Esso ^(f)) Baysilon MA:  ® Borchers Chemie GmbH

1% of the compound of Example 6 is added to the clearcoat, based on the solids content of the varnish.

For comparison, a clearcoat without the compound of Example 6 is used.

The clearcoat is diluted with Solvesso® 100 to spray viscosity and is applied by spraying to a prepared aluminium panel (®Uniprime Epoxy, silver-metallic basecoat) which is baked at 130° C., for 30 minutes, to give a dry film thickness of 40-50 μm of clearcoat.

The samples are then weathered in an Atlas ®UVCON weathering unit (UVB-313 lamps) in a cycle comprising UV irradiation at 70° C. for 8 hours and condensation at 50° C. for 4 hours.

The surface gloss (20° gloss as defined in DIN 67530) of the samples is then measured at regular intervals. The results are shown in the Table below:

TABLE 8 20° * gloss as defined in DIN 67530 after 0, 400, 800 and 1200 hours weathering in the  ® UVCON (UVB-313) Light stabilizer 0 hours 400 hours 800 hours 1200 hours None 91 59 27 — 1% of the compound of 91 82 55 22 Example 6

Higher gloss values indicate a good stabilization.

EXAMPLE J Stabilization of Photographic Layers

Chromogenic photographic layers are prepared by coating a gelatine emulsion containing silver bromide, yellow coupler and an additive on a polyethylene-coated paper.

The composition of the layer is as given in the following table, amounts are in mg/m².

Component Amount in the layer Gelatine 5150 AgBr 520 Yellow coupler CoupY1 835 Coupler solvent Solv1 278 Additive (see TABLE 9) 250 Hardener Ha1 300 Surfactant Su1 340

The layers are dried for 7 days in a ventilated cabinet. The dried samples are exposed to white light through a step wedge of 0.3 logE exposure steps and then developed with the P94 process for colour negative paper from ®Agfa-Gevaert, following the manufacturer's recommendations. After exposure and processing, the remission density of the yellow dye is measured in the blue channel. Subsequently, the samples are exposed in an ®Atlas weather-O-meter so as to receive 30 kJ/cm² light energy. The temperature is 43° C. and the relative humidity is 50%. The density loss starting from a density of 1 is determined. The results are listed in Table 9.

TABLE 9 Density loss (%) Additive (initial density = 1) none 42 Compound of Example 1 28 Compound of Example 6 32

The above table shows that additives of the present invention improve the light stability of the yellow photographic layer.

Components used: CoupY1: Compound of the formula

Solv1: Compound of the formula

Su1: Compound of the formula

Ha1: Compound of the formula

EXAMPLE K Light Stabilizing Action in Polypropylene Blue Plaques

1 g of the compound listed in Table 10, 0.67 g of tris(2,4-di-tert-butylphenyl) phosphite, 0.33 g of pentaerythritol tetrakis(3-(3,5-di-tert-butyl-4-hydroxy-phenyl)propionate), 1 g of calcium stearate and 1 g of Blue ®Filofin G are mixed in a turbomixer with 1000 g of polypropylene powder having a melt index of 3.0 (measured at 230° C. and 2.16 Kg).

The mixture is extruded at 200-230° C. to give polymer granules which are subsequently converted to plaques 2 mm thick, using an injection molding machine (®Negribossi—Italy) and working at a maximum temperature of 220° C.

The plaques thus prepared are mounted on a white card and exposed in a Weather-O-Meter 65 WR (ASTM D 2565-85) with a black panel temperature of 63° C.

The degree of chalking is measured, as an evaluation of surface degradation, on a sample taken after various light exposure times; a numeric scale, where 9 is the top value for the non exposed (non degraded) sample is adopted to rank the samples.

By way of comparison, a plaque prepared under the same conditions as indicated above, but without the addition of the stabilizer of the present invention, is exposed.

The results obtained are shown in Table 10.

TABLE 10 *)Chalking (number in brackets represents hours Compound of Weather-O-Meter exposure) Without stabilizer 5 (embrittled after 500 hours) Compound of Example 8 (after 1000 hours) 1 *)High numbers are desired. 

1. A compound of the formula (I)

wherein G₁, G₂, G₃ and G₄ are independently of one another C₁-C₁₈alkyl or C₅-C₁₂cycloalkyl or the radicals G₁ and G₂ and the radicals G₃ and G₄ form independently of one another, together with the carbon atom they are attached to, C₅-C₁₂cycloalkyl; R is hydrogen, C₁-C₁₈alkyl, oxyl, —OH, —CH₂CN, C₃-C₆alkenyl, C₃-C₈alkynyl, C₇-C₁₂phenylalkyl unsubstituted or substituted on the phenyl radical by C₁-C₄alkyl and/or C₁-C₄alkoxy; C₁-C₈acyl, C₁-C₁₈alkoxy, C₁-C₁₈hydroxyalkoxy, C₂-C₁₈alkenyloxy, C₅-C₁₂cycloalkoxy, C₇-C₁₂phenylalkoxy unsubstituted or substituted on the phenyl radical by C₁-C₄alkyl and/or C₁-C₄alkoxy; C₁-C₁₈alkanoyloxy, (C₁-C₁₈alkoxy)carbonyl, glycidyl or a group —CH₂CH(OH)(G) with G being hydrogen, methyl or phenyl; n is 1, 2, 3 or 4; and X is an organic radical of a valency equal to n with the proviso that X is different from methyl and ethoxycarbonyl; and when n is 2, 3 or 4, each of the radicals G₁, G₂, G₃, G₄ and R can have the same or a different meaning in the units of the formula


2. A compound according to claim 1 wherein when n is 1, X is C₂-C₁₈alkyl, C₂-C₁₈hydroxyalkyl, C₂-C₁₈alkyl interrupted by oxygen, sulphur or >N—R₀ with R₀ being as defined below; C₂-C₁₈alkynyl, C₂-C₁₈alkynyl, C₅-C₁₂cycloalkyl unsubstituted or substituted by —OH, C₁-C₄alkyl and/or C₁-C₄alkoxy; phenyl or C₇-C₉phenylalkyl unsubstituted or substituted on the phenyl radical by —OH, C₁-C₄alkyl and/or C₁-C₄alkoxy; or X is one of the groups of the formulae (II-a) to (II-m)

Y₁, Y₂, Y₅, Y₆, Y₇ and Y₉ are a direct bond, C₁-C₁₂alkylene, C₅-C₁₂cycloalkylene or phenylene; Y₃, Y₄, Y₈, Y₁₀, Y₁₁ and Y₁₂ are C₂-C₁₂alkylene, C₅-C₁₂cycloalkylene or phenylene; R₁, R₂, R₃, R₄, R₅, R₆, R₇ and R₁₃ are hydrogen, C₁-C₁₈alkyl, C₂-C₁₈alkyl interrupted by oxygen, sulphur or >N—R₀ with R₀ being as defined below; C₂-C₁₈alkynyl, C₂-C₁₈alkynyl, C₅-C₁₂cycloalkyl unsubstituted or substituted by C₁-C₄alkyl and/or C₁-C₄alkoxy; phenyl unsubstituted or substituted by C₁-C₄alkyl and/or C₁-C₄alkoxy; or C₇-C₉phenylalkyl unsubstituted or substituted on the phenyl radical by C₁-C₄alkyl and/or C₁-C₄alkoxy; Z₁, Z₂ and Z₃ are independently of one another —O— or >N—R₁₆; R₀, R₈, R₉, R₁₀, R₁₁, R₁₂, R₁₄, R₁₅ and R₁₆ are independently of one another hydrogen, C₁-C₁₈alkyl, C₃-C₁₈alkenyl, C₅-C₁₂cycloalkyl which is unsubstituted or substituted by C₁-C₄alkyl and/or C₁-C₄alkoxy; or C₇-C₉phenylalkyl which is unsubstituted or substituted on the phenyl radical by C₁-C₄alkyl and/or C₁-C₄alkoxy; with the proviso that the formula (II-b) is different from ethoxycarbonyl; when n is 2, X is C₂-C₁₂alkylene, C₂-C₁₆alkylene interrupted by oxygen, sulphur or >N—R₀′ with R₀′ being as defined below; C₂-C₁₂alkenylene, C₂-C₁₂alkynylene, C₅-C₁₂cycloalkylene, C₅-C₁₂cycloalkylene-(C₁-C₄alkylene)-C₅-C₁₂cycloalkylene, C₁-C₄alkylene-(C₅-C₁₂cycloalkylene)-C₁-C₄alkylene, phenylene, phenylene-(C₁-C₄alkylene)-phenylene or C₁-C₄alkylene-phenylene-C₁-C₄alkylene, or X is one of the groups of the formulae (III-a) to (III-j)

Y₁′, Y₁″, Y₂′, Y₂″, Y₅′, Y₅″, Y₆′, Y₆″, Y₇′ and Y₇″ are independently of one another a direct bond, C₁-C₁₂alkylene, C₅-C₁₂cycloalkylene or phenylene; Y₃′, Y₃″, Y₄′, Y₄″, Y₈′, Y₈″, Y₁₁′, Y₁₁″, Y₁₂′ and Y₁₂″ are independently of one another C₂-C₁₂alkylene, C₅-C₁₂cycloalkylene or phenylene; A₁, A₂, A₃, A₄, A₅, A₆, A₇, A₈ and A₉ are C₂-C₁₂alkylene, C₂-C₁₂alkylene interrupted by oxygen, sulphur or >N—R₀′ with R₀′ being as defined below, C₂-C₁₂alkenylene, C₂-C₁₂alkynylene, C₅-C₁₂cycloalkylene, C₅-C₁₂cycloalkylene-(C₁-C₄alkylene)-C₅-C₁₂cycloalkylene, C₁-C₄alkylene-(C₅-C₁₂cycloalkylene)-C₁-C₄alkylene, phenylene, phenylene-(C₁-C₄alkylene)-phenylene or C₁-C₄alkylene-phenylene-C₁-C₄alkylene; and A₁ and A₅ are additionally a direct bond; Z₁′, Z₂′ and Z₃′ are independently of one another —O— or >N—R₁₆′; and R₀′, R₁₄′ and R₁₆′ are independently of one another hydrogen, C₁-C₁₈alkyl, C₃-C₁₈alkenyl, C₅-C₁₂cycloalkyl which is unsubstituted or substituted by C₁-C₄alkyl and/or C₁-C₄alkoxy; or C₇-C₉phenylalkyl which is unsubstituted or substituted on the phenyl radical by C₁-C₄alkyl and/or C₁-C₄alkoxy: when n is 3, X is C₅-C₂₅alkantriyl, C₄-C₁₈triacyl or a group of the formula (IV);

Y₁₃′, Y₁₃″ and Y₁₃′″ are independently of one another C₂-C₁₂alkylene, C₅-C₁₂cycloalkylene or phenylene; Z₁″, Z₂″ and Z₃″ are independently of one another —O— or >N—R₁₆″; and R₁₆″ is hydrogen, C₁-C₁₈alkyl, C₃-C₁₈alkenyl, C₅-C₁₂cycloalkyl which is unsubstituted or substituted by C₁-C₄alkyl and/or C₁-C₄alkoxy; or C₇-C₉phenylalkyl which is unsubstituted or substituted on the phenyl radical by C₁-C₄alkyl and/or C₁-C₄alkoxy; and when n is 4, X is C₅-C₂₀alkantetrayl, C₆-C₂₂tetraacyl or a group of the formula (V)

Y₁₄′ and Y₁₄″ are independently of one another C₂-C₁₂alkylene, C₅-C₁₂cycloalkylene or phenylene; Z₁′″, Z₂′″, M and T are independently of one another —O— or >N—R₁₆′″, and M and T are additionally —S—; R₁₆′″ is hydrogen, C₁-C₁₈alkyl, C₃-C₁₈alkenyl, C₅-C₁₂cycloalkyl which is unsubstited or substituted by C₁-C₄alkyl and/or C₁-C₄alkoxy; or C₇-C₉phenylalkyl which is unsubstituted or substituted on the phenyl radical by C₁-C₄alkyl and/or C₁-C₄alkoxy; and q is an integer from 2 to
 12. 3. A compound according to claim 1 wherein G₁, G₂, G₃ and G₄ are methyl.
 4. A compound according to claim 1 wherein R is hydrogen, C₁-C₄alkyl, oxyl, —OH, C₃-C₆alkenyl, benzyl, C₁-C₈acyl, C₁-C₁₂alkoxy, C₁-C₁₂hydroxyalkoxy, C₂-C₈alkenyloxy or C₅-C₈cycloalkoxy.
 5. A compound according to claim 1 wherein R is hydrogen, methyl, allyl, acetyl, methoxy, propoxy, butoxy, octyloxy, hydroxybutoxy, 2-propenyloxy or cyclohexyloxy.
 6. A compound according to claim 1 wherein n is
 2. 7. A compound according to claim 2 wherein when n is 1, X is C₂-C₁₂alkyl, C₂-C₁₂hydroxyalkyl, C₂-C₁₂alkyl interrupted by oxygen or >N—R₀ with R₀ being as defined below; C₂-C₁₈alkenyl, C₅-C₈cycloalkyl unsubstituted or substituted by C₁-C₄alkyl; or benzyl unsubstituted or substituted on the phenyl radical by —OH and/or C₁-C₄alkyl; or X is one of the groups of the formulae (II-a) to (II-m); Y₁, Y₂, Y₅, Y₆, Y₇ and Y₉ are a direct bond, C₁-C₆alkylene, cyclohexylene or phenylene; Y₃, Y₄, Y₈, Y₁₀, Y₁₁ and Y₁₂ are C₂-C₆alkylene, cyclohexylene or phenylene; R₁, R₂, R₃, R₄, R₅, R₆, R₇ and R₁₃ are hydrogen, C₁-C₁₂alkyl, C₂-C₁₂alkyl interrupted by oxygen or >N—R₀ with R₀ being as defined below; C₂-C₁₈alkenyl, C₅-C₈cycloalkyl unsubstituted or substituted by C₁-C₄alkyl; phenyl unsubstituted or substituted by C₁-C₄alkyl; or benzyl unsubstituted or substituted on the phenyl radical by C₁-C₄alkyl; Z₁, Z₂ and Z₃ are independently of one another —O— or >N—R₁₆; R₀, R₈, R₉, R₁₀, R₁₁, R₁₂, R₁₄, R₁₅ and R₁₆ are independently of one another hydrogen, C₁-C₁₂alkyl, C₃-C18alkenyl, C₅-C₈cycloalkyl which is unsubstituted or substituted by C₁-C₄alkyl; or benzyl unsubstituted or substituted on the phenyl radical by C₁-C₄alkyl; with the proviso that the formula (II-b) is different from ethoxycarbonyl; when n is 2, X is C₂-C₆alkylene, C₂-C₁₆alkylene interrupted by oxygen or >N—R₀′ with R₀′ being as defined below; C₂-C₆alkenylene, cyclohexylene, cyclohexylene-(C₁-C₄alkylene)-cyclohexylene, C₁-C₄alkylene-cyclohexylene-C₁-C₄alkylene or C₁-C₄alkylene-phenylene-C₁-C₄alkylene, or X is one of the groups of the formulae (III-a) to (III-j); Y₁′, Y₁″, Y₂′, Y₂″, Y₅′, Y₅″, Y₆′, Y₆″, Y₇′ and Y₇″ are independently of one another a direct bond, C₁-C₆alkylene, cyclohexylene or phenylene; Y₃′, Y₃″, Y₄′, Y₄″, Y₈′, Y₈″, Y₁₁′, Y₁₁″, Y₁₂′ and Y₁₂″ are independently of one another C₂-C₆alkylene, cyclohexylene or phenylene; A₁, A₂, A₃, A₄, A₅, A₆, A₇, A₈ and A₉ are C₂-C₆alkylene, C₂-C₆alkylene interrupted by oxygen or >N—R₀′ with R₀′ being as defined below, C₂-C₆alkenylene, cyclohexylene, cyclohexylene-(C₁-C₄alkylene)-cyclohexylene, C₁-C₄alkylene-cyclohexylene-C₁-C₄alkylene or C₁-C₄alkylene-phenylene-C₁-C₄alkylene; and A₁ and A₅ are additionally a direct bond; Z₁′, Z₂′ and Z₃′ are independently of one another —O— or >N—R₁₆′; and R₀′, R₁₄′ and R₁₆′ are independently of one another hydrogen, C₁-C₁₂alkyl, C₃-C₁₈alkenyl, C₅-C₈cycloalkyl which is unsubstituted or substituted by C₁-C₄alkyl; or benzyl which is unsubstituted or substituted on the phenyl radical by C₁-C₄alkyl; when n is 3, X is C₅-C₁₀alkantriyl, an aliphatic C₄-C₁₈triacyl, an aliphatic C₆-C₁₈triacyl substituted by nitrogen; a cycloaliphatic C₆-C₁₈triacyl, an aromatic C₉-C₁₈triacyl, a heterocyclic C₉-C₁₈triacyl or a group of the formula (IV); Y₁₃′, Y₁₃″ and Y₁₃′″ are independently of one another C₂-C₆alkylene, cyclohexylene or phenylene; Z₁″, Z₂″ and Z₃″ are independently of one another —O— or >N—R₁₆″; and R₁₆″ is hydrogen, C₁-C₁₂alkyl, C₃-C₁₈alkenyl, C₅-C₈cycloalkyl which is unsubstituted or substituted by C₁-C₄alkyl; or benzyl which is unsubstituted or substituted on the phenyl radical by C₁-C₄alkyl; and when n is 4, X is C₅-C₁₀alkantetrayl, an aliphatic C₆-C₁₈tetraacyl, an aliphatic C₁₀-C₁₈tetraacyl substituted by nitrogen, a cycloaliphatic C₁₀-C₂₂tetraacyl, an aromatic C₁₀-C₁₈tetraacyl or a group of the formula (V); Y₁₄′ and Y₁₄″ are independently of one another C₂-C₆alkylene, cyclohexylene or phenylene; Z₁′″, Z₂′″, M and T are independently of one another —O— or >N—R₁₆′″, and M and T are additionally —S—; R₁₆′″ is hydrogen, C₁-C₁₂alkyl, C₃-C₁₈alkenyl, C₅-C₈cycloalkyl which is unsubstituted or substituted by C₁-C₄alkyl; or benzyl which is unsubstituted or substituted on the phenyl radical by C₁-C₄alkyl; and q is an integer from 2 to
 12. 8. A compound according to claim 2 wherein when n is 1, X is C₂-C₆alkyl, C₂-C₆hydroxyalkyl, C₂-C₆alkyl interrupted by oxygen; allyl, cyclohexyl, benzyl or one of the groups of the formulae (II-a) to (II-l); Y₁, Y₂, Y₅, Y₆, Y₇ and Y₉ are a direct bond, C₁-C₆alkylene, cyclohexylene or phenylene; Y₃, Y₄, Y₈, Y₁₀, Y₁₁ and Y₁₂ are C₂-C₆alkylene, cyclohexylene or phenylene; R₁, R₂, R₃, R₄, R₅, R₆, R₇ and R₁₃ are hydrogen, C₁-C₈alkyl, C₂-C₆alkyl interrupted by oxygen; allyl, cyclohexyl, phenyl or benzyl; Z₁, Z₂ and Z₃ are independently of one another —O— or >N—R₁₆; R₀, R₈, R₉, R₁₀, R₁₁, R₁₂, R₁₄, R₁₅ and R₁₆ are independently of one another hydrogen C₁-C₆alkyl, allyl, cyclohexyl or benzyl; with the proviso that the formula (II-b) is different from ethoxycarbonyl; when n is 2, X is C₂-C₆alkylene, C₂-C₁₄alkylene interrupted by oxygen or >N—R₀′; cyclohexylene or one of the groups of the formulae (III-a) to (III-j); Y₁′, Y₁″, Y₂′, Y₂″, Y₅′, Y₅″, Y₆′, Y₆″, Y₇′ and Y₇″ are independently of one another a direct bond, C₁-C₆alkylene, cyclohexylene or phenylene; Y₃′, Y₃″, Y₄′, Y₄″, Y₈′, Y₈″, Y₁₁′, Y₁₁″, Y₁₂′ and Y₁₂″ are independently of one another C₂-C₆alkylene, cyclohexylene or phenylene; A₁, A₂, A₃, A₄, A₅, A₆, A₇, A₈ and A₉ are C₂-C₆alkylene, C₂-C₆alkylene interrupted by oxygen; cyclohexylene or phenylene; and A₁ and A₅ are additionally a direct bond; Z₁′, Z₂′ and Z₃′ are independently of one another —O— or >N—R₁₆′; and R₀′, R₁₄′ and R₁₆′ are independently of one another hydrogen, C₁-C₆alkyl, allyl, cyclohexyl or benzyl; when n is 3, X is a group of the formula (IV); Y₁₃′, Y₁₃″ and Y₁₃′″ are independently of one another C₂-C₆alkylene, cyclohexylene or phenylene; Z₁″, Z₂″ and Z₃″ are independently of one another —O— or >N—R₁₆″; and R₁₆″ is hydrogen, C₁-C₆alkyl, allyl, cyclohexyl or benzyl; and when n is 4, X is a group of the formula (V); Y₁₄′ and Y₁₄″ are independently of one another C₂-C₆alkylene, cyclohexylene or phenylene; Z₁′″, Z₂′″, M and T are independently of one another —O— or >N—R₁₆′″; R₁₆′″ is hydrogen, C₁-C₆alkyl, allyl, cyclohexyl or benzyl; and q is an integer from 2 to
 12. 9. A compound according to claim 2 wherein when n is 2, X is C₂-C₆alkylene or C₂-C₁₄alkylene interrupted by oxygen or >N—R₀′; or X is a group of the formula (III-a), (III-b) or (III-j).
 10. A compound according to claim 1 wherein G₁, G₂, G₃ and G₄ are methyl; R is hydrogen, methyl, allyl, acetyl, propoxy or 2-propenyloxy; when n is 1, X is a group of the formula (II-a) or (II-l);

Y₁ is a direct bond or C₁-C₆alkylene; R₁ is C₁-C₈alkyl; Z₁, Z₂ and Z₃ are >N—R₁₆; R₁₄, R₁₅ and R₁₆ are independently of one another hydrogen or C₁-C₆alkyl; and Y₁₂ is C₂-C₆alkylene; when n is 2, X is C₂-C₆alkylene, C₂-C₁₄alkylene interrupted by 2>N—H; or a group of the formula (III-b) or (III-j);

Y₂′, Y₂″, Y₁₂′ and Y₁₂″ are independently of one another C₁-C₆alkylene; A₂ is C₂-C₆alkylene; Z₁′, Z₂′ and Z₃′ are independently of one another >N—R₁₆′; and R₁₄′ and R₁₆′ are independently of one another hydrogen or C₁-C₆alkyl; when n is 3, X is a group of the formula (IV);

Y₁₃′, Y₁₃″ and Y₁₃′″ are independently of one another C₂-C₆alkylene; Z₁″, Z₂″ and Z₃″ are a group >N—H; and when n is 4, X is a group of the formula (V);

Y₁₄′ and Y₁₄″ are independently of one another C₂-C₆alkylene; Z₁′″, Z₂′″, M and T are a group >N—H; and q is an integer from 2 to
 6. 11. A compound according to claim 1 wherein G₁, G₂, G₃ and G₄ are methyl; R is hydrogen, methyl, allyl, acetyl, propoxy or 2-propenyloxy; n is 2; X is C₂-C₆alkylene or a group of the formula (III-b);

Y₂′ and Y₂″ are independently of one another C₁-C₆alkylene; and A₂ is C₂-C₆alkylene.
 12. A compound according to claim 1 wherein G₁, G₂, G₃ and G₄ are methyl; R is hydrogen, methyl or allyl; n is 1; X is C₂-C₆alkyl, C₂-C₆hydroxyalkyl or a group of the formula (II-b) or (II-m); Y₂ is C₁-C₆alkylene; and R₂ is hydrogen.
 13. A compound according to claim 1, which corresponds to the formula


14. A compound according to claim 1, which corresponds to the formula


15. A composition containing an organic material susceptible to degradation induced by light, heat or oxidation and at least one compound of the formula (IA);

wherein G₁, G₂, G₃ and G₄ are independently of one another C₁-C₁₈alkyl or C₅-C₁₂cycloalkyl or the radicals G₁ and G₂ and the radicals G₃ and G₄ form independently of one another, together with the carbon atom they are attached to, C₅-C₁₂cycloalkyl; R is hydrogen, C₁-C₁₈alkyl, oxyl, —OH, —CH₂CN, C₃-C₆alkenyl, C₃-C₈alkynyl, C₇-C₁₂phenylalkyl unsubstituted or substituted on the phenyl radical by C₁-C₄alkyl and/or C₁-C₄alkoxy; C₁-C₈acyl, C₁-C₁₈alkoxy, C₁-C₁₈hydroxyalkoxy, C₂-C₁₈alkenyloxy, C₅-C₁₂cycloalkoxy, C₇-C₁₂phenylalkoxy unsubstituted or substituted on the phenyl radical by C₁-C₄alkyl and/or C₁-C₄alkoxy; C₁-C₁₈alkanoyloxy, (C₁-C₁₈alkoxy)carbonyl, glycidyl or a group —CH₂CH(OH)(G)with G being hydrogen, methyl or phenyl; n is 1, 2, 3 or 4; and X is an organic radical of a valency equal to n; and when n is 2, 3 or 4, each of the radicals G₁, G₂, G₃, G₄ and R can have the same or a different meaning in the units of the formula

with the proviso that a photographic material containing a compound of the formula

is disclaimed.
 16. A composition according to claim 15 wherein when n is 1, X is C₁-C₁₈alkyl, C₂-C₁₈hydroxyalkyl, C₂-C₁₈alkyl interrupted by oxygen, sulphur or >N—R₀ with R₀ being as defined below; C₂-C₁₈alkenyl, C₂-C₁₈alkynyl, C₅-C₁₂cycloalkyl unsubstituted or substituted by —OH, C₁-C₄alkyl and/or C₁-C₄alkoxy; phenyl or C₇-C₉phenylalkyl unsubstituted or substituted on the phenyl radical by —OH, C₁-C₄alkyl and/or C₁-C₄alkoxy; or X is one of the groups of the formulae (II-a) to (II-m)

Y₁, Y₂, Y₅, Y₆, Y₇ and Y₉ are a direct bond, C₁-C₁₂alkylene, C₅-C₁₂cycloalkylene or phenylene; Y₃, Y₄, Y₈, Y₁₀, Y₁₁ and Y₁₂ are C₂-C₁₂alkylene, C₅-C₁₂cycloalkylene or phenylene; R₁, R₂, R₃, R₄, R₅, R₆, R₇ and R₁₃ are hydrogen, C₁-C₁₈alkyl, C₂-C₁₈alkyl interrupted by oxygen, sulphur or >N—R₀ with R₀ being as defined below; C₂-C₁₈alkenyl, C₂-C₁₈alkynyl, C₅-C₁₂cycloalkyl unsubstituted or substituted by C₁-C₄alkyl and/or C₁-C₄alkoxy; phenyl unsubstituted or substituted by C₁-C₄alkyl and/or C₁-C₄alkoxy; or C₇-C₉phenylalkyl unsubstituted or substituted on the phenyl radical by C₁-C₄alkyl and/or C₁-C₄alkoxy; Z₁, Z₂ and Z₃ are independently of one another —O— or >N—R₁₆; R₀, R₈, R₉, R₁₀, R₁₁, R₁₂, R₁₄, R₁₅ is and R₁₆ are independently of one another hydrogen, C₁-C₁₈alkyl, C₃-C₁₈alkenyl, C₅-C₁₂cycloalkyl which is unsubstituted or substituted by C₁-C₄alkyl and/or C₁-C₄alkoxy; or C₇-C₉phenylalkyl which is unsubstituted or substituted on the phenyl radical by C₁-C₄alkyl and/or C₁-C₄alkoxy; when n is 2, X is C₂-C₁₂alkylene, C₂-C₁₆alkylene interrupted by oxygen, sulphur or >N—R₀′ with R₀′ being as defined below; C₂-C₁₂alkenylene, C₂-C₁₂alkynylene, C₅-C₁₂cycloalkylene, C₅-C₁₂cycloalkylene-(C₁-C₄alkylene)-C₅-C₁₂cycloalkylene, C₁-C₄alkylene-(C₅-C₁₂cycloalkylene)-C₁-C₄alkylene, phenylene, phenylene-(C₁-C₄alkylene)-phenylene or C₁-C₄alkylene-phenylene-C₁-C₄alkylene, or X is one of the groups of the formulae (III-a) to (III-j)

Y₁′, Y₁″, Y₂′, Y₂″, Y₅′, Y₅″, Y₆′, Y₆″, Y₇′ and Y₇″ are independently of one another a direct bond, C₁-C₁₂alkylene, C₅-C₁₂cycloalkylene or phenylene; Y₃′, Y₃″, Y₄′, Y₄″, Y₈′, Y₈″, Y₁₁′, Y₁₁″, Y₁₂′ Y₁₂″ are independently of one another C₂-C₁₂alkylene, C₅-C₁₂cycloalkylene or phenylene; A₁, A₂, A₃, A₄, A₅, A₆, A₇, A₈ and A₉ are C₂-C₁₂alkylene, C₂-C₁₂alkylene interrupted by oxygen, sulphur or >N—R₀′ with R₀′ being as defined below, C₂-C₁₂alkenylene, C₂-C₁₂alkynylene, C₅-C₁₂cycloalkylene, C₅-C₁₂cycloalkylene-(C₁-C₄alkylene)-C₅-C₁₂cycloalkylene, C₁-C₄alkylene-(C₅-C₁₂cycloalkylene)-C₁-C₄alkylene, phenylene, phenylene-(C₁-C₄alkylene)-phenylene or C₁-C₄alkylene-phenylene-C₁-C₄alkylene; and A₁ and A₅ are additionally a direct bond; Z₁′, Z₂′ and Z₃′ are independently of one another —O— or >N—R₁₆′; and R₀′, R₁₄′ and R₁₆′ are independently of one another hydrogen, C₁-C₁₈alkyl, C₃-C₁₈alkenyl, C₅-C₁₂cycloalkyl which is unsubstituted or substituted by C₁-C₄alkyl and/or C₁-C₄alkoxy; or C₇-C₉phenylalkyl which is unsubstituted or substituted on the phenyl radical by C₁-C₄alkyl and/or C₁-C₄alkoxy: when n is 3, X is C₅-C₂₅alkantriyl, C₄-C₁₈triacyl or a group of the formula (IV);

Y₁₃′, Y₁₃″ and Y₁₃′″ are independently of one another C₂-C₁₂alkylene, C₅-C₁₂cycloalkylene or phenylene; Z₁″, Z₂″ and Z₃″ are independently of one another —O— or >N—R₁₆″; and R₁₆″ is hydrogen, C₁-C₁₈alkyl, C₃-C₁₈alkenyl, C₅-C₁₂cycloalkyl which is unsubstituted or substituted by C₁-C₄alkyl and/or C₁-C₄alkoxy; or C₇-C₉phenylalkyl which is unsubstituted or substituted on the phenyl radical by C₁-C₄alkyl and/or C₁-C₄alkoxy; and when n is 4, X is C₅-C₂₀alkantetrayl, C₆-C₂₂tetraacyl or a group of the formula (V)

Y₁₄′ and Y₁₄″ are independently of one another C₂-C₁₂alkylene, C₅-C₁₂cycloalkylene or phenylene; Z₁′″, Z₂′″, M and T are independently of one another —O— or >N—R₁₆′″, and M and T are additionally —S—; R₁₆′″ is hydrogen, C₁-C₁₈alkyl, C₃-C₁₈alkenyl, C₅-C₁₂cycloalkyl which is unsubstited or substituted by C₁-C₄alkyl and/or C₁-C₄alkoxy; or C₇-C₉phenylalkyl which is unsubstituted or substituted on the phenyl radical by C₁-C₄alkyl and/or C₁-C₄alkoxy; and q is an integer from 2 to
 12. 17. A composition according to claim 15 wherein the organic material is a synthetic polymer.
 18. A composition according to claim 15 wherein the organic material is a pigmented vulcanized rubber.
 19. A composition according to claim 15 wherein the organic material is a polyolefin.
 20. A composition according to claim 15 wherein the organic material is a thermoplastic polyolefin (TPO) or acrylonitrile-butadiene-styrene (ABS).
 21. A coating containing a compound of the formula (IA) as defined in claim
 15. 22. A recording material containing at least one compound of the formula (IA) as defined in claim 15; with the proviso that the compound of the formula

is disclaimed.
 23. A method for stabilizing an organic material against degradation induced by light, heat or oxidation, which comprises incorporating into said organic material at least one compound of the formula (IA) as defined in claim 15; with the proviso that the compound of the formula (IA) is different from

when the organic material is a photographic material.
 24. A method for preparing a compound of the formula (IA) as defined in claim 15, which comprises reacting a compound of the formula (S-1)

wherein G₁, G₂, G₃, G₄ and R are as defined in claim 15, with a compound of the formula (S-2) [HAL

_(n)x  (S-2) wherein n and X are as defined in claim 15 and HAL is halogen, in an inert organic solvent in the absence of a base. 